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  OXFORD MEDICAL PUBLICATIONS

  THE SURGERY OF
  THE SKULL AND BRAIN


  PUBLISHED BY THE JOINT COMMITTEE OF
  HENRY FROWDE AND HODDER & STOUGHTON
  AT THE OXFORD PRESS WAREHOUSE
  FALCON SQUARE, LONDON, E.C.


  OXFORD MEDICAL PUBLICATIONS

  THE SURGERY OF
  THE SKULL AND BRAIN

  BY

  L. BATHE RAWLING, F.R.C.S.

  SURGEON, WITH CHARGE OF OUT-PATIENTS, SENIOR DEMONSTRATOR OF PRACTICAL
  SURGERY
  DEMONSTRATOR OF OPERATIVE SURGERY, ST. BARTHOLOMEW’S HOSPITAL
  LATE HUNTERIAN PROFESSOR, ETC.

  LONDON
  HENRY FROWDE HODDER & STOUGHTON
  OXFORD UNIVERSITY PRESS WARWICK SQUARE, E.C.
  1912


  OXFORD: HORACE HART
  PRINTER TO THE UNIVERSITY




PREFACE


This work on the Surgery of the Skull and Brain is based on experience
derived, and on research carried out, during the past ten years.

Cranio-Cerebral Surgery, though still in its infancy, has progressed
with leaps and bounds during the past few years. This book represents
the most modern aspects of the case and is brought up to date by means
of a recent visit to some of the leading surgical clinics of the United
States of America.

I have realized to the full the difficulties of the task which I have
undertaken, but have every confidence that they have been overcome and
that a reasonable measure of success has been obtained. With this
anticipation, this work on the Surgery of the Skull and Brain is offered
to the Profession.

  L. BATHE RAWLING.

  _April 1912._




CONTENTS


  CHAPTER I

                                                                    PAGE

  CRANIO-CEREBRAL TOPOGRAPHY                                           1


  CHAPTER II

  THE SPECIAL TECHNIQUE IN OPERATIONS ON THE SKULL AND BRAIN          10


  CHAPTER III

  CEPHALOCELES, BIRTH-FRACTURES AND HÆMORRHAGES, HYDROCEPHALUS AND
  DERMOIDS                                                            31


  CHAPTER IV

  FRACTURES OF THE SKULL                                              68


  CHAPTER V

  INTRACRANIAL INJURIES. EXTRA- AND SUB-DURAL HÆMORRHAGES. INJURY TO
  THE BRAIN                                                          135


  CHAPTER VI

  THE REMOTE EFFECTS OF HEAD-INJURY                                  182


  CHAPTER VII

  TUMOURS OF THE BRAIN                                               210


  CHAPTER VIII

  THE INFECTIVE DISEASES OF THE BRAIN AND MENINGES: ABSCESS OF THE
  BRAIN, MENINGITIS, LATERAL AND CAVERNOUS SINUS THROMBOSIS, HERNIA
  CEREBRI                                                            247


  CHAPTER IX

  BULLET-WOUNDS OF THE SKULL AND BRAIN                               294


  CHAPTER X

  TRIGEMINAL NEURALGIA                                               306


  CHAPTER XI

  TUMOURS OF THE SKULL-BONES                                         325


  INDEX                                                              335




LIST OF ILLUSTRATIONS


  FIGS.                                                            PAGES
   1 and 2. Cranio-cerebral topography                              2, 3
   3. The cortical motor and sensory areas                             8
   4 and 5. The scalp-tourniquet                                  14, 15
   6. Cushing’s ‘clips’                                               18
   7. Hudson’s trephine                                               20
   8. The hand-trephine                                               21
   9 and 10. The technique of trephining                              22
  11-16. Instruments used in trephining                           23, 24
  17-19. The formation of an osteoplastic flap                    26, 27
  20. An occipital cephalocele                                        33
  21. A cephalocele over the anterior fontanelle                      35
  22. An occipital cephalocele                                        37
  23. A depressed birth-fracture                                      45
  24 A and B. A case of depressed birth-fracture, before and after
      operation                                                       47
  25. To illustrate the effects and position of a birth-hæmorrhage    53
  26. The author’s operation for Hydrocephalus internus               64
  27. The conversion of Hydrocephalus internus into cephalocele       65
  28. Illustrating the lines along which forces received on the vault
      are transmitted to the base                                     69
  29 A and B. The base of the skull and the base as seen on
      transillumination                                           70, 71
  30. Plan of the base of the skull                                   77
  31. To illustrate the relation of basic fractures to cranial
      nerves                                                          81
  32-37. The lines pursued by basic fractures                       83-8
  38 A and B. To illustrate the probable source of profuse
      hæmorrhage from the ear                                         97
  39. To show the relation of a typical basic fracture to the middle
      ear and its adjuncts                                           103
  40 and 41. To show the relation of basic fractures to the petrous
      bone                                                      104, 105
  42. A comminuted fracture of the skull                             112
  43 A and B. An explosive fracture of the vault of the skull        113
  44. A temperature chart illustrating the changes in temperature
      observed in head-injuries                                      117
  45-48. Intermusculo-temporal cerebral decompression           122, 123
  49 A and B. The elevation of a depressed fracture of the vault     131
  50 A and B. The inner aspect of the skull and the same seen on
      transillumination                                              137
  51. To illustrate compression of the brain as produced by an
      extra-dural hæmorrhage from the middle meningeal artery        141
  52 A and B. The operative treatment of middle meningeal
      hæmorrhage                                                144, 145
  53. A basic fracture with laceration of both carotid arteries      148
  54. A basic fracture with laceration of the cavernous sinus        149
  55. A basic fracture with laceration of both lateral sinuses       151
  56 A and B. The operative treatment of subdural hæmorrhage    156, 157
  57. The areas concerned in speech expression                       163
  58. The cortical motor and sensory areas                           165
  59. The König-Müller osteoplastic flap                             197
  60. The author’s method of covering in a gap in the skull          199
  61. A case of traumatic orbital aneurysm                           207
  62. A glioma of the brain                                          211
  63. A sarcoma of the brain                                         211
  64. An endothelioma of the dura mater                              212
  65. A fibroma of the dura mater                                    212
  66. An acoustic tumour                                             213
  67. Symmetrical tuberculomata                                      214
  68. The cortical motor and sensory areas                           220
  69. The visual paths                                               223
  70. A pituitary tumour                                             226
  71 A, B and C. The exposure of a tumour by osteoplastic flap  230, 231
  72. Combined flap formation and decompression                      235
  73 A, B, C and D. The exposure of a cerebellar tumour by
      craniectomy                                                 239-41
  74 A and B. To illustrate the extension of disease from the tympanic
      cavity and the surgical anatomy of that region (after Hunter
      Tod)                                                           251
  75. A large right-sided temporo-sphenoidal abscess                 256
  76. To illustrate the pressure effects of a temporo-sphenoidal
      abscess                                                        257
  77. A cerebellar abscess                                           259
  78. To illustrate diagrammatically the symptoms observed in
      cerebellar abscess formation (after Luciani)                   261
  79. The exposure of a temporo-sphenoidal abscess                   265
  80. The ‘radical’ mastoid operation (after Hunter Tod)             269
  81. Exploration for a temporo-sphenoidal abscess (after Hunter
      Tod)                                                           270
  82. Exploration for a cerebellar abscess (after Hunter Tod)        271
  83. A fracture of the anterior fossa which was followed by the
      development of meningitis                                      275
  84. Basal meningitis secondary to temporo-sphenoidal abscess       277
  85 A and B. To illustrate the exposure of the lateral sinus (after
      Hunter Tod)                                                    285
  86. A case of Hernia cerebri and the abscess after removal         292
  87. Diagrammatic illustration of the three forms of ‘gutter’
      fracture                                                       297
  88. Diagrammatic representation of the effects produced on bone
      and brain by a perforating bullet-wound                        299
  89 A and B. Sheen’s bullet probe, forceps, and telephone
      bullet-detector                                           302, 303
  90. To illustrate the operations on the Gasserian ganglion         317
  91. To illustrate the operations for exposure of the Gasserian
      ganglion                                                       321
  92. Ivory exostoses of the skull                                   326
  93. The development of the frontal bone                            327
  94. An exostosis of the orbit                                      330
  95. An extrinsic sarcoma of the skull                              331
  96. An intrinsic sarcoma of the skull                              333




  THE SURGERY OF
  THE SKULL AND BRAIN




CHAPTER I

CRANIO-CEREBRAL TOPOGRAPHY


The surgeon who is called upon to carry out operations on the skull and
brain must possess an accurate knowledge of the anatomy of the parts
involved. Added to this, he must have at his command some simple method
of depicting on the surface of the skull the more important structures.

The more complicated systems of cranio-cerebral topography are of little
practical value to the surgeon. Simplicity is essential, and the
following outline will be found to furnish an adequate practical guide.

Firstly, the skull can be divided into two lateral halves by the
surface-marking of the superior longitudinal venous sinus.


=The superior longitudinal sinus.= This sinus originates at the crista
galli and, passing backwards along the attached margin of the falx
cerebri, terminates at the internal occipital protuberance. It may be
represented by a line drawn from the base of the nose (the nasion), over
the vertex of the skull, to the external occipital protuberance (the
inion)--this line corresponding in its course to the occasionally
persistent metopic suture between the two halves of the frontal bone, to
the sagittal suture between the parietal bones, and to the middle line
of the upper or tabular portion of the occipital bone.

Secondly, each lateral half of the skull can be subdivided into supra-
and infratentorial regions by a line which marks the external attachment
of the tentorium cerebelli; in other words, by the line of the lateral
sinus.


=The lateral sinus.= This sinus is represented by a line presenting a
slight upward convexity, which is drawn from the external occipital
protuberance to the upper and posterior part of the mastoid process of
the temporal bone.

[Illustration: FIG. 1. CRANIO-CEREBRAL TOPOGRAPHY. 1, The nasion; 2, The
inion; 3, The mid-point between nasion and inion; 4, The Rolandic
fissure; 5, The superior temporal crest; 6, The inferior temporal crest;
7, The Sylvian point; 8, The anterior horizontal limb of the Sylvian
fissure; 9, The vertical limb of the Sylvian fissure; 10, The posterior
horizontal limb of the Sylvian fissure; 11, The parietal prominence; 12,
The malar tubercle; 13, The lambda; 14, The first temporo-sphenoidal
sulcus; 15, The external parieto-occipital sulcus; 16, The lateral
sinus; 17, 17, 17, The level of the base of the cerebrum; 18, The
external auditory meatus; 19, 19, Reid’s base-line. (_Reproduced, by the
permission of Mr. H. K. Lewis, from the author’s work on ‘Landmarks and
Surface-markings’._)]

[Illustration: FIG. 2. CRANIO-CEREBRAL TOPOGRAPHY. 1, 1, Reid’s
base-line; 2, 2, A line parallel to the above at the level of the
supra-orbital margin; 3, The middle meningeal artery; 4, The anterior
branch; 5, 5, 5, The three sites for trephining; 6, The posterior
branch; 7, The site for trephining; 8, The point for trephining to reach
the descending horn of the lateral ventricle; 9, The lateral sinus; 10,
The inion; 11, The mastoid process; 12, Macewen’s suprameatal triangle;
12_a_, The mastoid antrum; 12_b_, The facial nerve; 13, The suprameatal
and supramastoid crests; 14, 14, The temporal crest; 15, The temporal
fossa; 16, The external angular frontal process; 17, The tendo-oculi
attachment; 18, The lachrymal groove. (_Reproduced, by the permission of
Mr. H. K. Lewis, from the author’s work on ‘Landmarks and
Surface-markings’._)]


=The infratentorial region.= The cerebellum lies wholly beneath the
tentorium cerebelli, and it is obvious that, in operations carried out
over this portion of the brain, the surgeon is limited in his field of
exposure, above by the line of the lateral sinus, and on either side by
the posterior border of the mastoid process. The division between the
halves of the cerebellum may be represented by a line drawn vertically
downwards from the external occipital protuberance to the nuchal region.
This line also represents the surface-marking of the occipital sinus and
falx cerebelli.


=The supratentorial region.= Brief allusion must be made to certain
landmarks that aid in the representation of structures situated in this
region:--


(_a_) _The external angular frontal process._ The suture between the
external angular frontal process and the corresponding process of the
malar bone lies immediately above the central point of the outer border
of the orbital cavity.


(_b_) _The malar tubercle._ A slight prominence on the posterior border
of the frontal process of the malar bone, about ¹⁄₄ inch below the
external angular frontal process.


(_c_) _The temporal crest._ A prominent ridge that is directed upwards
and backwards from the external angular frontal process. The crest cuts
across the lower portion of the parietal bone, passing below the
parietal prominence, and curves downwards towards the upper and
posterior portion of the mastoid process. It terminates by becoming
continuous with the upper root of the zygomatic process. The crest
consists of two parts, the upper and lower temporal crests. To the upper
is attached the temporal fascia, to the lower the temporal muscle. The
lower crest is almost invariably the more prominent.


(_d_) _The parietal prominence._ The central and most prominent part of
the parietal bone. It indicates the point at which ossification
commenced, and lies about ³⁄₄ inch above the termination of the
posterior horizontal limb of the fissure of Sylvius.


(_e_) _The zygoma._ When traced in the backward direction, the zygoma is
found to divide immediately in front of the ear into three roots, of
which the anterior, merging into the eminentia articularis, and the
middle, aiding in the formation of the post-glenoid process, are of no
practical utility in surface-marking. The upper or posterior root sweeps
backwards above the external auditory meatus to become continuous with
the suprameatal and supramastoid crests, the former of which forms the
upper boundary of _Macewen’s suprameatal triangle_, a triangular
depression at the upper and posterior border of the external auditory
meatus. This triangle may be taken as representing the opening of the
mastoid antrum into the middle ear.

These landmarks having been determined, the following structures may be
mapped out on the surface of the skull.


=The middle meningeal artery.= This artery is given off from the
internal maxillary; after a short extra-cranial course it enters the
skull through the foramen spinosum, and soon divides into two main
terminal branches. The site of division corresponds to a point situated
just above the centre of the zygoma.

The _anterior branch_ passes at first in a forward and upward direction
towards the anterior inferior angle of the parietal bone, and then turns
upwards and backwards towards the vertex of the skull. The main ‘danger
zone’ in the course of this vessel may be mapped out by taking points
which lie respectively 1, 1¹⁄₂, and 2 inches behind the external angular
frontal process and an equal distance above the upper border of the
zygoma. A line uniting these three points represents that part of the
anterior division of the middle meningeal artery which is most liable to
injury and which therefore most frequently requires exposure.

The uppermost point may, however, be regarded as the ‘site of election’
for exposure of the artery, as, in trephining over either of the two
lower points, difficulty may be experienced in the removal of the disk
of bone, since the posterior border of the great wing of the sphenoid
tails off on to the anterior inferior angle of the parietal bone in such
a manner that to effect a clean removal of the disk is often impossible.
Another disadvantage to trephining low down lies in the fact that in
about 30 to 40 per cent. of cases the artery occupies, in that
situation, a canal in the bone.

The _posterior branch_ passes almost horizontally backwards, parallel to
the zygoma and supramastoid crest, towards the posterior inferior angle
of the parietal bone. The vessel can readily be exposed by trephining
over the point at which a line drawn backwards from the upper border of
the orbit, parallel to Reid’s base-line,[1] cuts another line directed
vertically upwards from the posterior border of the mastoid process.

Both branches of the middle meningeal artery possess important relations
to the cortex cerebri, the anterior branch passing upwards in relation
to the precentral or motor area, traversing, from below upwards, the
motor speech area (on the left side of the head), the centres for the
movements of the face, upper extremity, trunk, and lower extremity. The
posterior branch, on the other hand, passes backwards in relation to the
temporo-sphenoidal lobe, one of the so-called ‘silent areas’ of the
brain. Throughout their course the middle meningeal vessels lie between
the dura mater and the bone.


=The lower limit of the cerebrum.= The lower limit of the cerebrum can
be mapped out in the following manner: From a point situated about ¹⁄₂
inch above the nasion a line is drawn outwards which follows the curve
of the upper border of the orbit as far as the external angular frontal
process, thence curving upwards and backwards to the Sylvian point (see
below). The temporo-sphenoidal lobe sweeps forwards to the posterior
border of the malar bone, and its lower limit lies practically flush
with the upper margin of the zygoma. At and behind the ear the lower
limit of the cerebrum corresponds to the suprameatal and supramastoid
crests, subsequently following the curve of the lateral sinus from the
mastoid process to the external occipital protuberance.


=The Sylvian point and fissure.= The Sylvian point represents the site
of divergence of the three limbs of the Sylvian fissure. It lies 1¹⁄₄
inches behind the malar tubercle and 1¹⁄₂ inches above the upper border
of the zygoma. The main posterior horizontal limb passes backwards and
upwards to a second point situated ³⁄₄ inch below the parietal
prominence.

The vertical limb is directed upwards for about 1 inch, whilst the
anterior horizontal limb passes forwards for about the same distance.


=The fissure of Rolando.= This, from a surgical point of view, the most
important fissure of the brain, is represented as follows: A point is
taken in the median antero-posterior line which lies ¹⁄₂ inch behind the
mid-point between nasion and inion, and from this point a line is drawn,
for 3¹⁄₂ to 4 inches, towards the mid-point of the zygoma. This line is
inclined to the median antero-posterior line at an angle of 67¹⁄₂°
(three-quarters of a right angle).


=The parieto-occipital and first temporo-sphenoidal fissures.= In the
representation of these two fissures, two points require to be
determined--the malar tubercle and the lambda. Allusion has already been
made to the former; the latter is usually readily located as the
point of intersection of the sagittal and lambdoid sutures. A line
uniting these two points corresponds in its middle third to the
temporo-sphenoidal fissure, and in its posterior inch or so to the
external parieto-occipital sulcus, a fissure separating the occipital
and parietal lobes of the brain.


=The cortical motor and sensory areas.= The researches of Sherrington
and Grünbaum,[2] Campbell,[3] and others tend to show that the _cortical
motor areas_ are situated entirely anterior to the central fissure or
fissure of Rolando, extending above well over on to the mesial aspect of
the brain, though not so far as the calloso-marginal fissure, and in the
downward direction to within a short distance of the fissure of Sylvius.
In the posterior direction the motor area includes the anterior boundary
and part of the bottom of the fissure of Rolando, whilst in front it
spreads, by means of gyri annectantes, on to that part of the brain
which lies anterior to the precentral sulcus. The anterior termination
is indefinite, but the motor strip is, on an average, not more than ³⁄₄
inch in breadth.

The genua of the Rolandic fissure are said to bear a more or less
definite relation to the motor areas. In my experience, however, they
are too variable, and any importance which might obtain is further
diminished by the fact that the surgeon should never rest content with
that limited exposure of the brain which was so much in vogue till
recent years. The suspected region is widely exposed by osteoplastic
flap, and if doubt exists as to the particular part of cortex exposed
the question is accurately settled by faradization.

This motor strip corresponds, from above downwards, to the movements of
the contralateral lower extremity (toe to hip), trunk, upper extremity
(shoulder to fingers), neck and face. It is a point of some general
utility to bear in mind that the temporal crest intervenes approximately
between the regions responsible for the movements of the upper extremity
(above the crest) and those for the movements of the head and face
(below the crest).

[Illustration: FIG. 3. THE CORTICAL MOTOR AND SENSORY AREAS.]

On the left side of the head--in normal right-handed individuals--the
_motor speech area of Broca_ corresponds to the third left frontal
convolution, in the angle between the anterior and posterior horizontal
limbs of the Sylvian fissure.

The ‘primary registration’ of ‘_common sensation_’ occurs in the
post-central gyrus, immediately posterior to the fissure of Rolando.
This tactile area occupies a position behind the fissure of Rolando
similar in extent to that occupied by the motor area in front. It
commences at the bottom of the fissure of Rolando and extends backwards
over rather more than half the exposed area of the post-central
convolution. It reaches down to near the Sylvian fissure and extends
over on to the mesial aspect of the brain. Furthermore, it is probable
that sensation in any given part lies on more or less the same level as
the corresponding motor area.

Immediately posterior to the tactile area and occupying the posterior
and upper part of the post-central convolution, the area responsible for
_muscle-sense_ is situated.

=Stereognosis=--memory pictures, object perception, &c.--is referred to
the superior parietal lobe.

=Primary visual impressions= are received in the occipital lobe, more
especially on the mesial aspect thereof.

Finally, the four areas concerned in =speech=--motor speech, writing,
reading, and hearing--are anatomically separated from one another and
yet closely associated, so much so that one can hardly be involved
without the other. The motor speech centre of Broca has already been
mentioned as occupying--in right-handed individuals--the posterior part
of the third left frontal convolution. Writing lies immediately above
and in front, in the posterior part of the middle frontal gyrus,
auditory impressions are received in the posterior and upper part of the
first temporo-sphenoidal lobe, whilst the power of reading is dependent
on the integrity of the supramarginal and angular gyri (see also Fig.
57).

=Smell and Taste= lie in close relation to the anterior pole of the
temporo-sphenoidal lobes.

[1] Reid’s base-line is a line drawn around the skull, starting in front
at the lower border of the orbit and passing through the central point
of the external auditory meatus.

[2] _Proceedings and Philosophic Transactions of the Roy. Soc._, 1901.

[3] _Localization of Cerebral Function._ Camb. Univ. Press, 1905.




CHAPTER II

THE SPECIAL TECHNIQUE IN OPERATIONS ON THE SKULL AND BRAIN


=Preparatory treatment.= Where possible at least two or three days
should elapse between the admission of the patient and the day of
operation. During this period the patient should be confined to bed with
all possible cheerful surroundings. The bowels are regulated and the
diet restricted.

The extent to which the scalp should be shaved and the time at which
this procedure should be carried out vary according to the circumstances
of the case. Much depends on the sex and age of the patient and the
nature of the proposed operation. Insomuch, however, as it is always
inadvisable to prolong the period of anæsthesia, it follows that the
shaving should be carried out previous to the operation. With regard to
extent, each case must be judged on its own merits. For instance,
considerable concession must be made in the case of a young woman on
whom the surgeon proposes to carry out a subtemporal decompression
operation, and in the case of a neurotic or elderly patient who is the
subject of trigeminal neuralgia. There can, however, be no question that
the limitation of operative field advocated by some surgeons is fraught
with considerable risk from the point of view of wound infection.

If the question be discussed with the patient the surgeon will find the
ground cut away from beneath his feet, and that he has to make
considerable and inadvisable concessions. Taking everything into
consideration, although it is seldom necessary to shave the whole head,
I am accustomed to order such preparation as will allow of a very wide
margin. To shave the whole head is not only unnecessary but is also
exceedingly distasteful to the patient. The front, back, or side of the
head should be prepared only--on the morning of the operation, so as to
allow of a comfortable night’s rest. After shaving, the scalp is
thoroughly cleansed with soap and water, and the head surrounded by a
sterilized towel. The final skin sterilization is carried out when the
patient is under the anæsthetic.

The iodine method has always given satisfactory results, the skin being
painted, half an hour previous to operation, with a 2¹⁄₂ per cent.
solution of iodine, and again after the administration of the
anæsthetic. Still, I cannot avoid a certain penchant for the older
method--sponging with ether to remove the fats, washing with a 1 in 500
spirit solution of biniodide of mercury, and finally douching with a
weaker mercury solution.


=Precautions against the development of shock.= It is almost inevitable
that all serious head-operations should be associated with some degree
of shock, though, from my experience, I am convinced that, with due
precautions, it is far less serious than is generally supposed. The
development of shock is very largely dependent on the amount of blood
lost during the operative procedures. The various methods adopted to
control hæmorrhage are enumerated later. In addition, attention should
be paid to the following details:--

1. Half an hour before the operation an injection of a quarter of a
grain of morphia should be given hypodermically. The addition of
one-hundredth of a grain of atropin, recommended by some surgeons,
interferes somewhat, by its action on the pupil, with the data deemed
necessary for the administration of the anæsthetic.

2. The theatre should be maintained at a temperature between 65 and 75
degrees Fahrenheit. The table should be suitably warmed.

3. The patient’s body should be covered with warm blankets, and, in the
more serious cases, the lower extremities may be bandaged, from below
upwards.

It has been recommended that the brain, if exposed, should be protected
from the cooling effects of the atmosphere by irrigation with saline
solution at a temperature between 110 and 115 degrees Fahrenheit.
Personally I prefer to keep the operative field as dry as possible.

An assistant should be told off, whose duty lies in keeping a record
both of blood-pressure and pulse-rate. The lowering of blood-pressure is
the surest guide to the surgeon of approaching danger.

It is often considered that rapidity of operation is essential. There
can be no greater error. To ensure success the utmost care must be taken
to control the loss of blood, for which it is essential that each step
of the operation should be carried out deliberately and carefully.


=The anæsthetic.= Needless to say, it is essential that the surgeon
should have at his disposal an anæsthetist of great experience in head
operations.

Ether is regarded with favour in the United States, and in other
countries, but we prefer chloroform on the ground that, by its lowering
effect on the blood-pressure, there is less venous oozing, and added to
this there is probably less tendency to post-operative vomiting. I have
recently had the opportunity of seeing the open ether method as carried
out in the States, on one occasion for an operation lasting four hours,
and in this and in other cases the patient left the operation table in
excellent condition, recovering also rapidly from the effects of the
anæsthetic.

The lowering of blood-pressure as produced by chloroform might be
advanced as an argument against the use of that drug, shock being the
greatest danger to be feared in these operations. Still, I must say that
I prefer chloroform so long as it is administered by a skilled
anæsthetist.

In any case, it is advisable to have oxygen ready to hand.


=The position of the patient.= Special tables have been invented and
special positions advised. Thus, the dental-chair position is
recommended for operations on the Gasserian ganglion, and, in cerebellar
operations, it is urged that the patient should be turned on his face,
the forehead resting on a tripod, the shoulders on supports fastened to
the head of the table. Personally, I do not consider that any special
arrangements are required in the majority of cases. Much can be done
with sand-bags and firm pillows. Even in the exposure of one cerebellar
hemisphere I prefer to utilize the semi-prone position.

In bilateral cerebellar exposure, however, the patient must be placed on
his face, the forehead resting on special supports, and the shoulders on
props or pillows so as to allow of free entry of air into the chest. In
such cases the anæsthetic is administered from below.

I am not enthusiastic over the so-called dental-chair position, but the
operating table should be constructed in such a manner that the head and
shoulders of the patient can be well raised, the body being inclined to
the floor at an angle of about 30-40 degrees.


=Preparation of the operative field.= When the patient is fully under
the anæsthetic, the final cleansing of the scalp is carried out and the
operative field cut off from all possible sources of infection. In the
States, in Cushing’s clinic, the anæsthetist is completely covered with
a large sterilized sheet, which is fastened to the head of the patient.
In this country we prefer that our anæsthetist should have full
knowledge of the progress of the operation, and I think that the
advantages are with us. In any case, the whole head is enveloped in
gauze, two or three layers thick and about 18 inches square. This sheet
is thrown over the patient’s head and maintained in position by means of
the scalp-tourniquet (see pp. 14, 15). Around this sterilized towels are
arranged, either fastened to one another or stitched to the scalp. When
the operation is conducted in the temporal region the towels, unless
fastened to the skin by means of a few sutures or safety-pins, tend to
become displaced, and by so doing add to the risk of wound infection.


THE CONTROL OF HÆMORRHAGE


=Hæmorrhage from vessels of the scalp.= All surgeons must have
appreciated the difficulty attendant on the application of forceps to,
and the ligature of, divided scalp-vessels. The patient may lose a
considerable quantity of blood, and much valuable time will be wasted
before the more essential part of the operation is commenced. All this
can, under ordinary circumstances, be avoided by the use of the
scalp-tourniquet. As used by Cushing it consists of a rubber ring
fashioned after the style of an Esmarch’s tourniquet, encircling the
head and passing from the lower frontal region in front, above the ears,
to the lower occipital region behind. A median tape, passing from
glabella to occiput, prevents any tendency for the tourniquet to slip
down over the eyes, at the same time acting as a convenient landmark for
the superior longitudinal sinus.

The tourniquet, when applied with the correct pressure, should, under
ordinary circumstances, completely control all hæmorrhage from the
divided scalp-vessels. It should be noted, however, that bleeding will
be rather increased than otherwise if the tourniquet be so loosely
applied as to impede the venous return without compressing the scalp
arteries. A little experience will soon enable the operator to gauge the
requisite pressure.

[Illustration: FIG. 4. THE SCALP-TOURNIQUET. _Front View._]

[Illustration: FIG. 5. THE SCALP-TOURNIQUET. _Back View._]

There is one other exception to the satisfactory working of the
scalp-tourniquet. In the presence of a superficial cerebral tumour,
especially when of a malignant nature, the normal communication between
the intra- and extra-cranial vascular systems may be so exaggerated that
those scalp-vessels which receive diploic and emissary venous
communications will give rise to some trouble. This difficulty should be
overcome--not by rapidity in the formation and turning down of the
flap--but by clipping each vessel as exposed or divided, by the
application of pressure and by foraminal occlusion (see also p. 17).

I found Cushing’s tourniquet rather inconvenient in its application,
and, after various modifications, am accustomed to use the one depicted
in the illustration. It consists of two flat metal bands connected
posteriorly by a strong rubber connecting link, the two bands passing in
front through a metal fixation piece possessing a screw which, when
tightened up, allows of the maintenance of the desired pressure. The
median tape, previously mentioned, helps to keep the tourniquet in
position.

The tourniquet is applied as follows: the whole head is enveloped in
gauze--two or three layers thick, and cut to the size and shape of a
large handkerchief. The tourniquet is slipped over the head, as low
down as possible, and then tightened up. The median tape, having a loop
behind through which the tourniquet passes, is laid in the middle line
and tied round the screw on the fixation piece.

The gauze should then be moistened with saline solution or some mild
antiseptic, so that it clings tightly to the underlying scalp and
becomes sufficiently translucent to allow of the recognition of any
underlying landmarks that may have been previously mapped out with the
scalpel, iodine, silver nitrate, or aniline pencil.

The scalp-flap is then framed by incisions carried down to the bone,
through gauze and scalp, in one sweep. The flap is turned down and
covered with gauze. By the adoption of this method hæmorrhage from
scalp-vessels is efficiently controlled and the risk of wound infection
is reduced to a minimum.

After the completion of the operation, the scalp-flap is approximated
and sewn into position, first by numerous buried fine silk sutures
bringing together the aponeurotic layer of the scalp, and finally by a
few silk or salmon-gut sutures passed through the skin itself. Gauze
dressings are applied, the tourniquet loosened, and a roll-gauze bandage
quickly applied circumferentially around the head, low down over the
forehead and occipital region. This roll bandage in reality takes the
place of the tourniquet, but is, of course, applied with moderate
pressure only.

If the wool and bandage now applied over all should include the ears,
these two organs should be well covered with vaseline. Few things are
more uncomfortable to the patient than the contact of wool and bandage
to the ears.

The tourniquet should be utilized whenever possible. In operations,
however, that are conducted near the base of the skull--subtemporal
decompression, cerebellar exploration, &c.--the surgeon, in his effort
at hæmostasis, must rely on the application of digital pressure on
either side of the incision, the more careful exposure of the vessels,
and the application of forceps as soon as they are seen or divided, or
by the utilization of Vorschütz’s hæmostatic safety-pins.

Other methods of controlling scalp-bleeding are as follows:--

1. Kredel’s hæmostatic sutures, passed with a large curved needle which
slides along the bone and emerges about 5 to 7 cm. from the point of
introduction. The silk ligatures are then tied over metal plates, so
curved as to lie flush with the surface of the skull in the particular
region involved. Four of these plates would be used in the formation of
an osteoplastic flap, one on the distal side of each of the three scalp
incisions, and one along the base of the flap.

2. The enclosure of the proposed incision by a running suture which,
passing down to the bone, emerges about 1 inch further on, then so to
speak repeating itself in part until the whole region is surrounded. The
ligatures are then tightened up. This method takes some time in its
application, and presents no advantages over the scalp-tourniquet.

3. The blocking of the main arterial supply--temporal, occipital, and
supra-orbital vessels--by modified safety-pins, mass ligatures, &c.
Arterial compression by means of the modified safety-pin as suggested by
Vorschütz will be found most useful in those operations in which the
scalp-tourniquet cannot be utilized--subtemporal decompression, &c.


=Hæmorrhage from the bone.= Severe bleeding may take place from the
mastoid and other emissary veins, and from the open mouths of those
abnormally dilated diploic and emissary veins so often encountered in
the exposure of an underlying dural or superficial cerebral tumour. The
foramina in the bone, when exposed, must be occluded as quickly as
possible. For this purpose we have the following methods at our
disposal--plugging with small bone or wooden pegs, blockage with minute
plugs of cotton-wool, and the utilization of Horsley’s wax, smeared over
the part and well pressed home.

Hæmorrhage may also occur from the bone during trephining, more
especially when the operation is conducted over that part of the
anterior division of the middle meningeal artery which runs through a
channel in the spheno-parietal region. Here the disk of bone should be
removed as quickly as possible and the channel plugged with pegs,
cotton-wool, or wax.

Oozing from the raw surface of the cut bone is controlled by rubbing in
aseptic wax, or by the crushing together of the inner and outer tables.

=Hæmorrhage from the dural vessels.= In this case the bleeding may occur
from three sources, meningeal veins--often of considerable size when
related to neighbouring tumour-formation--the middle meningeal artery,
and the venous sinuses of the brain.

Hæmorrhage from meningeal veins may be arrested by one or other of the
following methods:--

1. Gentle pressure as applied either by dry gauze, or wet gauze soaked
in saline solution at a temperature between 110 and 115 degrees
Fahrenheit.

2. The application of a piece of muscle to the bleeding-point. This
method was, I believe, first introduced by Sir Victor Horsley. Some
muscle is usually available for the purpose, usually the temporal
muscle. A small portion of muscle is snipped off, spread out as a flat
muscular pad, the bleeding area dried, and the graft quickly applied. It
soon adheres, and usually arrests the hæmorrhage.

3. The application of a ligature. This method is placed last, being the
most difficult. It is usually necessary to underrun the bleeding-point
with a fine needle threaded with the finest of silk. It presents the
disadvantage in that the needle may perforate the dura mater and
puncture one of the superficial cerebral veins.

[Illustration: FIG. 6. CUSHING’S CLIPS. A, The holder of the clips; B, A
clip ready to be applied; C, Two clips applied to the middle meningeal
artery.]

Hæmorrhage from the middle meningeal artery may be controlled by
ligature or torsion, and added to these methods we have one other,
recently introduced by Cushing--silver wire ‘clips’. These clips are
U-shaped, loaded on a magazine, picked up as required in the jaws of a
specially indented forceps, and clipped on to the vessel--usually one on
either side of the bleeding-point.

Hæmorrhage from venous sinuses is dealt with on p. 150.


=Hæmorrhage from the superficial vessels of the brain.= This form of
hæmorrhage, one of the most troublesome complications arising in
head-operations, most commonly results from hasty or careless opening of
the dura mater. Thus, when the dura is incised in a case of greatly
increased intracranial pressure, the brain herniates suddenly outwards,
and the incautious use of the knife will damage one of the dilated
superficial cortical veins. The dura should always be opened with the
greatest care, the knife being passed lightly over the membrane till the
pia-arachnoid is exposed, when the dural margins are lifted up with
small tenaculum forceps and the membrane slit up with blunt-pointed
scissors or on a grooved director.

In the event of injury, the bleeding may often be controlled by light
pressure with dry gauze, or wet gauze wrung out in hot saline solution
as described above. If this fails, a very fine silk ligature may be
passed beneath the vessel on either side of the site of bleeding. This
procedure is not easy to accomplish, the tissues are so soft and
friable. However, every effort must be made to arrest the bleeding, for
not only does the hæmorrhage obscure the field of operation, but the
presence of a blood-clot beneath the dura mater will lead at a later
date to the formation of adhesions between the various membranes of the
brain--a potent cause of headache, epilepsy, &c.


THE OPENING OF THE SKULL

Two methods are adopted in the exposure of meninges and
brain--craniectomy and craniotomy.

=Craniectomy= implies the formation of a scalp-flap, exposure of the
bone, trephining of the skull, and enlargement of the gap to the
required size and shape.

=Craniotomy= implies the formation of a flap of scalp and bone in one,
and the exposure of an area of dura and brain directly proportionate to
the size of the bone-flap.


=Craniectomy.= After the application of protective gauze and tourniquet,
the scalp-flap is framed according to the requirements of the case. If
the tourniquet is used, the knife is entered at one extremity of the
proposed flap, carried down to the bone--through gauze and scalp in
one--and the incision completed in a single sweep. Under other
circumstances, digital pressure is applied to the main flap-supplying
vessel, e.g. the temporal artery over the base of the zygoma, or else
Kredel’s clamps or Vorschütz’s hæmostatic safety-pins are passed in such
a manner as to control bleeding from the main supplying vessel. In the
event of bleeding, the surgeon goes along quietly, deepening his
incision and seizing each vessel as exposed.

In turning down the scalp-flap it is usually recommended that the
pericranium should be included. This is quite unnecessary, and, under
certain circumstances, should certainly be omitted (see p. 129). It
should be stripped away from the underlying bone as required.

[Illustration: FIG. 7. HUDSON’S TREPHINE. Showing the usual method of
using the spiral perforator, spiral follower, and enlarging burr.]

The trephining may be carried out with the hand-trephine, or by means of
saws, burrs, and trephines driven by electricity. With the exception of
a few words on Hudson’s trephine, I do not propose to discuss the
relative advantages and disadvantages of these mechanically-driven
instruments. I hold the opinion that the hand-driven instrument is
sufficiently rapid in its work, that it is infinitely safer, and that
the surgeon should accustom and perfect himself with those instruments
which are to him most convenient and most portable. He will not always
be conducting his operations in a perfectly equipped hospital, much of
his work will be carried out in the nursing home or in the country.
Whatever method be adopted, the operator should use those instruments to
which he is most accustomed.

Hudson’s trephine is shaped after the style of the carpenter’s brace and
is fitted with three cutting heads--the perforator, the follower, and
the enlarging burr. It is claimed that injury to the dura and brain is
impossible, the instrument becoming automatically locked so soon as the
resistance of the internal table is overcome, a thin film of bone being
pushed in front of the advancing head. I have had the opportunity of
using this instrument, and so far as my experience goes it answers all
requirements. Still, I prefer the ordinary hand-trephine so long as it
satisfies certain requirements. It must be of simple mechanism and
strong, the handle of good size and shaped to fit the hand, the shaft
and head so interlocked as to allow of no independent movement, and the
hollow head sharply toothed and bevelled externally, in continuity with
the teeth, for a distance of half an inch. The bevelling is so arranged
that the actual cutting process is only effected during supination of
the hand and forearm. The pin of the trephine should not project beyond
the cutting edge for a greater distance than about ·2cm. This pin should
be readily removable.

[Illustration: FIG. 8. THE HAND-TREPHINE.]

The pattern which I am accustomed to use is depicted in Fig. 8. The
trephines are kept in three sizes--diameter ¹⁄₂, 1, and 1¹⁄₂ inches. The
intermediate size is used for ordinary trephining, the small one for the
formation of the osteoplastic flap, the large for the removal of a disk
of bone which includes within its circumference the area involved in
some depressed and punctured fractures (see p. 133).

[Illustration: FIG. 9.

FIG. 10.

TO SHOW THE TECHNIQUE OF TREPHINING. Fig. 9 illustrates the act of
trephining for cerebellar exposure. Fig. 10 shows a trephine-disk to one
side of a depressed fracture.]

The site of trephining may be fixed by the introduction of a bradawl
through the scalp, so indenting the external table that the spot can be
verified on turning down the scalp-flap. The pin of the trephine is
there applied, and the trephine directed at right angles to the
surface of the skull, or at that angle which is suited to the region
attacked. The pin is discarded when a sufficient groove has been
attained. The trephine must be kept under perfect control, muscular
effort only being required during the act of supination.

[Illustration: FIG. 11. HORSLEY’S DISK OR BONE ELEVATOR.]

[Illustration: FIG. 12. HORSLEY’S DURAL SEPARATOR.]

[Illustration: FIG. 13. KEEN-HOFFMANN’S CRANIECTOMY FORCEPS.]

The firm nature of the external table will be readily appreciated; so
soon as this resistance is overcome the trephine will be felt to be
cutting its way through a softer structure, whilst the increased
bone-dust and venous oozing will make it evident that the instrument is
biting its way through the diploic tissue. Greater resistance is again
encountered on meeting the internal table, warning the operator that the
time has come when greater care must be exercised. The bone-dust must be
wiped away, the teeth of the trephine cleansed with nail-brush or
sponge, and the depth of the groove estimated. The groove should be of
the same depth throughout its circumference, or of that depth which is
suited to the part involved.

The readiness of the disk for removal is best demonstrated by digital
pressure. When it gives to that pressure, whether in whole or in part,
the elevator may be applied and the fragment removed.

In the temporal and cerebellar regions special care is required by
reason of the absence of diploic tissue.

It is impossible to lay too much stress on the necessity of avoiding
injury to underlying dura and meningeal vessels. Injury to these
structures not infrequently upsets the whole plan of campaign.

[Illustration: FIG. 14.

LANE’S FULCRUM CRANIECTOMY FORCEPS.]

[Illustration: FIG. 15.

HORSLEY’S GOUGE FORCEPS.]

[Illustration: FIG. 16. DE VILBISS’S CRANIECTOMY FORCEPS.]


_The enlargement of the trephine hole to the required size and shape._
Previous to any attempt at enlargement of the trephine hole, the dura
mater must be separated from the bone with the aid of Horsley’s dural
separator or other suitable instrument. Of the many patterns of
craniectomy forceps, the following will be found to suit all
requirements:--


_Keen-Hoffmann._ The visceral blade is introduced between the dura and
the bone and ‘morcellement’ carried out. It is essential that the
surgeon should not be too greedy, resting content with the removal of
small fragments at a time.


_Lane’s fulcrum forceps._ They possess great mechanical advantage and
are mainly suited for the rapid removal of large portions of bone.


_Horsley’s nibbling or rongeur forceps._ This instrument is mainly
utilized in the smoothing and refreshing of sharp edges of bone, and in
the ‘morcellement’ of the thinner portions of the skull--temporal and
cerebellar regions.


_De Vilbiss’s forceps._ A clever contrivance whereby the operator is
enabled to cut a narrow channel in the bone. Mainly utilized in the
formation of the osteoplastic flap.


=Craniotomy.= Craniotomy, or osteoplastic resection of the skull, was
first carried out by Wagner. It is proposed to describe that method only
which, by experience, has been found to meet all requirements--the
formation of the osteoplastic flap by means of the hand-trephine,
Gigli’s saw, and de Vilbiss’s forceps.

The protective gauze dressing and scalp-tourniquet are applied as
before. A large

  ______
  \    / -shaped
   \  /

incision is made in such a manner as to include the area which it is
desired to expose. The two vertical limbs of the incision should
converge to such a degree as to allow of the subsequent ready fracture
of the flap along its base. The knife is entered at one extremity,
carried down to the bone, and the three incisions rapidly made, one
after the other. Along the line of each of the three incisions, the
pericranium is stripped away from the bone so as to allow of adequate
exposure. At the anterior and posterior angles of the flap the tissues
are retracted a little more, permitting the application of a half-inch
diameter trephine. Here the two trephine-holes are bored--with the usual
precautions against damage to the dura mater--and the two disks of bone
elevated and removed.

Between these two trephine-holes the dura mater is separated from the
bone and the special director introduced, entering at the one hole,
emerging at the other, and lying throughout between the dura and the
bone. The saw is now passed along the groove of the director, the
handles affixed, and the bone intervening between the two trephine-holes
divided, not straight out to the surface, but bevelled or cut in such an
oblique manner that the bone-flap, when replaced, rests on a ledge (see
Figs. 17-19). The sawing process generates considerable heat, and the
assistant should be instructed to keep up irrigation with saline
solution or sterilized water. The sawing is carried out by steady
side-to-side traction, without jerks; if the saw breaks, the special
handle may be attached, thus obviating the necessity of introducing a
new saw.

[Illustration: FIG. 17. FIRST STAGE IN THE FORMATION OF AN OSTEOPLASTIC
FLAP. Gigli’s saw, protected from the dura mater by the special
director, passing between the two trephine-holes. For further
description, see text.]

[Illustration: FIG. 18. SECOND STAGE IN THE FORMATION OF AN OSTEOPLASTIC
FLAP. The bone-flap turned down and the dura mater exposed.]

[Illustration: FIG. 19. THIRD STAGE IN THE FORMATION OF AN OSTEOPLASTIC
FLAP. The dural flap turned down and the brain exposed. Note the
relation of the scalp, bone, and dural incisions to one another.]

The dura is now separated from the bone along the line of the two
vertical incisions, and the visceral blade of de Vilbiss’s forceps
insinuated beneath the bone, starting at one trephine-hole and working
downwards to the lower limit of the incision. It is essential that the
operator should be satisfied with the ‘morcellement’ of small portions
of bone at each bite of the instrument. At the lower end of each of
the vertical incisions the forceps is directed inwards for ¹⁄₄ to ¹⁄₂
inch so as to weaken the base of the flap.

To lift up the osteoplastic flap, a stout elevator or spatula is
introduced beneath the bone at its upper part, leverage applied, and, as
soon as sufficient elevation has been attained, the dura mater carefully
separated from the whole of the under aspect of the flap. The flap is
then grasped at its upper part with both hands and, with a quick but
forcible jerk, broken across at its base, the assistant at the same time
aiding the correct linear fracture of the bone by a flat spatula applied
to the outer aspect of the base of the flap. Insomuch as the flap is
most usually framed in the parieto-temporal region--for the exposure of
the motor area--the base of the flap, being formed from the squamous
portion of the temporal bone, is comparatively weak. Fracture is then
readily obtained. Under other circumstances the base may be sufficiently
weakened by the application of the de Vilbiss forceps or by the use of
the Gigli saw.

The bone-flap is thrown back and enveloped in gauze. Its basal region is
examined for a possible injury to meningeal vessels. In the event of
such complications the bleeding vessel is clipped, ligatured, or
underrun. Possibly some branch of the anterior division of the middle
meningeal artery, running in an osseous canal, may require to be
controlled by foraminal occlusion--with a wooden match, bone peg,
cotton-wool, or aseptic wax.

In comparing the =relative advantages and disadvantages= of craniectomy
and craniotomy, although there are certain definite contra-indications
to the latter method, yet craniotomy should always be carried out when
the surgeon desires to expose a large surface area of brain, more
especially in the exposure of a tumour diagnosed to lie in relation to
the motor cortex. Even if the operator should be unsuccessful in his
exploration, or, if finding the tumour, should deem it irremovable, the
dura can be sewn up and the bone-flap replaced, resting on its bevelled
edge, with little defect in the skull and a normal surface contour.

The three main disadvantages to craniotomy are as follows:--(1) the
operation can seldom be done under much less than thirty minutes; (2)
there is some slight risk of complication through injury to the middle
meningeal artery; and (3) the dura mater may be so adherent to the bone
as to be torn in the process of flap-elevation. Time, however, is
usually of little importance; bleeding from the middle meningeal artery
may be controlled, and dural lesions may be avoided by careful
technique. In general, the advantages of osteoplastic resection greatly
outweigh the disadvantages.

The more definite contra-indications to the formation of the bone-flap
are as follows:--

1. This operation is unnecessarily severe in most cases of intracranial
hæmorrhage, e. g. from the middle meningeal artery. It is also usually
impracticable by reason of the associated damage to the bones of the
vault and base.

2. It is contra-indicated in operations conducted for the exposure of
the Gasserian ganglion, its root and its branches (trigeminal
neuralgia). In these operations it is essential that the operator should
get down as low as possible towards the base of the skull.

3. It is contra-indicated in operations conducted in the cerebellar
region. Even after cerebellar exposure by craniectomy, the surgeon is
working in a sufficiently confined space. The presence of a bone-flap
only adds further difficulty and complication. Added to this is the fact
that the thin wall of the cerebellar fossa is not adapted to
osteoplastic flap-formation.


=Opening the dura mater.= Reference has already been made to the great
importance of opening the dura in such a manner as to avoid injury to
the underlying superficial cerebral vessels (see p. 19). It may be
incised in a crucial manner or by flap-formation. Flaps are usually to
be preferred if the surgeon desires to have the widest possible view of
the brain surface. In the formation of the flap, advantage should be
taken of the vessels that minister to its vitality. Thus, in the lateral
region of the head, the base lies below, the middle meningeal artery
supplying the flap. Under special circumstances, the blood-supply may be
disregarded; the flap never sloughs, so far as my experience goes.


=Sewing up the dura mater.= Considerable difficulty may be experienced
in sewing up the dura--by reason of the bulging of the brain. How these
difficulties may be overcome is dealt with on p. 236. The edges should
be united by numerous fine silk sutures.


=Replacement of the osteoplastic flap and sewing up.= The flap is
replaced, care being taken that its lower or fractured edge does not
injure the dura mater. The aponeurotic and subcutaneous tissues of the
scalp-flap are sewn up in the manner stated on p. 16.


=After-treatment.= Whether the operation be carried out by craniectomy
or craniotomy, the patient is put back to bed in the so-called head-down
position, the lower end of the bed being raised at least a foot above
the level of the head. In the event of shock, a hypodermic injection of
a ¹⁄₄ gr. of morphia should be given, the lower extremities may be
bandaged firmly from below upwards, and saline infusions administered,
preferably per rectum.




CHAPTER III

CEPHALOCELES. BIRTH-HÆMORRHAGES. BIRTH-FRACTURES. DERMOIDS.
HYDROCEPHALUS


CEPHALOCELES

The term ‘Cephalocele’ has been applied to all those tumours which
project through a gap or deficiency in the bones of the vault and base
of the skull. The tumour may be congenital or traumatic in origin: the
membranes of the brain may alone protrude (meningocele), or the tumour
may be composed of normal or altered brain-substance: all the varying
conditions, however, are included under one term--=cephalocele=.
Congenital and traumatic cephaloceles differ, however, so markedly from
one another, both with regard to their pathology and treatment, that
they must be considered separately.


=Congenital cephaloceles.= Billroth and the late Professor von Bergmann
were the first to narrate cases in which this deformity was present,
Lyssenkow[4] added much to the previous records, and de Quèrvain,[5] by
prolonged researches, drew further attention to the subject.

Lyssenkow divided the congenital variety into two main
groups--exencephaly and cephalocele--the former resulting from a general
error in development (the ‘Acrania’ of Muscatelle), the latter a partial
or local developmental failure. In =exencephaly= there is an extensive
gap in the vault of the skull, the remainder of the skull being
microcephalic in nature, the brain projecting outwards in a varying
degree, and the ventricular spaces distended with fluid. In
=cephaloceles= the hole in the skull is usually circumscribed, although
the sutures may be widely separated and the ventricles distended with
fluid, yet both skull and brain may be normally developed in all other
respects.


=Exencephaly= presents but few points of surgical interest, insomuch as
the condition is barely compatible with life.


=Cephaloceles= occupy a very different position. The condition is by no
means confined to man, and many instances are recorded as occurring
throughout the animal kingdom. Norsa Gurrieri,[6] for instance, records
a case occurring in the embryo of Mus decumanus vel albinus. The same
writer insists that the developmental error involves bones of either
cartilaginous or membranous origin, and that the atrophic condition of
the bone is the primary cause and the ectopia of the brain a secondary
result.

Lyssenkow,[7] after careful investigation of tumours removed by
operation and after death, found scattered nerve-fibres, fat-cells,
striated muscle and vessels--the products, therefore, of both ectoderm
and mesoderm. He also observed the frequent occurrence of an intimate
union or fusion between the cephalocele and the overlying integument,
and, in consequence, the theory was formulated that the greater number
of cephaloceles were in reality cephalomata or true teratoid tumours.

It would appear, therefore, that a cephalocele results from the
incomplete cutting off of the neural canal in the head region of the
embryo from the overlying epiblast, with consequent fusion between the
primary neural tube (from which the brain is developed) with the
primordial mesoblastic membranous cranium (from which the membranes are
developed), and with the overlying epiblastic layer (from which the
epidermal portion of the scalp is developed). In consequence of this
localized fusion of layers, the outer dermic coat (from which the
membranous skull is developed) fails to form. Bony defects therefore
exist through which brain-matter protrudes, the projecting portion often
being intimately attached to the skin, and containing not only
epiblastic elements, but also mesoblastic tissue from irregular
occlusion of the same. The mesoblastic involvement is proved by the
presence in the tumour of muscle tissue, vessels, &c.


=Position of the tumour.= The tumour may project through the vault or
base of the skull. In the former case, it is almost invariably situated
in close relation to the middle line of the skull, from nasion to below
the inion.

[Illustration: FIG. 20. AN OCCIPITAL CEPHALOCELE. (For further
description, see text.)]

1. _Occipital cephaloceles_--the commonest variety--occupy,
anatomically, two positions (1) between the two lower segments of the
occipital bone (inferior occipital cephaloceles), often involving the
foramen magnum and sometimes complicated by a condition of cervical
spina bifida, and (2) between the two upper segments of the occipital
bone (superior occipital cephaloceles), occasionally involving the
posterior fontanelle.

The tumour may possess a broad base or may be definitely pedunculated.
In the former instance the gap in the bone may be of considerable size
and the margins everted: in the latter case, the hole may be quite
small.

The deformity is frequently associated with other congenital
defects--hydrocephalus, microcephalus, spina bifida, hare lip, hernia,
and talipes.

2. _Sincipital cephaloceles_ occur next in order of frequency. The
tumour projects between the nasal bones and the nasal process of the
superior maxilla (naso-frontal), between the nasal process of the
maxilla and the orbital plates of the ethmoid (naso-ethmoidal), or
between the nasal bones (nasal).

[Illustration: FIG. 21. A CEPHALOCELE OVER THE ANTERIOR FONTANELLE.

(For further description, see text.)]

3. More rarely, the tumour overlies the _anterior or posterior
fontanelle_. A case of this nature is depicted in Fig. 21, the tumour,
situated over the anterior fontanelle, bulging over the temporal and
frontal regions to a remarkable extent.

4. _Basal cephaloceles_ protrude through the cartilaginous base of the
skull, either through the cribriform plate of the ethmoid, between the
pre- and basi-sphenoid, or between the basi-sphenoid and basi-occiput,
often projecting as a polypoid growth in the nose or naso-pharynx.

  An interesting case of basal hernia was reported by von Mayer.[8] The
  child, 3 days old, was admitted with a tumour projecting into the
  right nostril, covered with mucous membrane, translucent, encrusted
  with scabs, pedunculated, and closely resembling a nasal polypus. The
  possibilities were fully recognized and all necessary precautions
  taken. The right half of the nose was turned back as a flap, the
  tumour isolated, ligatured, and removed. Death occurred after six
  weeks. An oval hole was found in the left half of the cribriform plate
  through which the dura mater projected and to the margins of which the
  membrane was firmly adherent. The pedicle contained ganglion-cells and
  nerve-fibres, whilst the parts removed showed, from without inwards,
  mucous membrane, dura mater, arachnoid, pia, and glial tissue.


=Size, structure, and contents.= Sincipital cephaloceles are usually
quite small, but the occipital variety and those situated in the region
of the anterior fontanelle frequently attain a great size (see Figs.
20-22).

[Illustration: FIG. 22. AN OCCIPITAL CEPHALOCELE. (For further
description, see text.)]

It is not always possible to determine whether the tumour consists
of a mere outward protrusion of membranes (meningocele), or
whether brain-matter enters into the formation of the tumour
(meningo-encephalocele). Fluctuation, translucency, and pulsation are
all points to be investigated. All these features are, however,
deceptive, and several cases are on record in which operative measures
were carried out under the impression that the surgeon had to deal with
a pure meningocele, and in which it was afterwards found that
brain-matter formed the basis of the swelling.

When the tumour is large, the skin adherent, when no pedicle is present,
when fluctuation and pulsation are absent, and when the tumour is of
firm consistency, then it is practically certain that brain-matter
shares largely in the formation of the tumour. On the other hand, it is
not unusual to find that the brain projects markedly outwards without
resulting in any symptoms of brain irritation: fluctuation and pulsation
are also not infallible signs, since the brain may occupy the base of
the tumour, ‘corking-up’ the gap in the bone, or the brain may be so
thinned by ventricular distension that a mere shell of cerebral matter
lies beneath the scalp-covering.

Looking at the question from all points of view, it may be accepted that
most cephaloceles contain either true brain-matter or the mixed
epiblastic and mesoblastic elements described by Lyssenkow.

The following case serves to illustrate some of these facts:[9]--

  The child was 3 months old, and presented a tumour, the size of an
  orange, situated between the occipital protuberance and the nape of
  the neck. The mass was pedunculated, the stalk being about the size of
  a four-shilling piece in diameter. It was soft, translucent,
  irreducible, and swelled up on coughing. An attempt at removal was
  carried out, and, after incising the outermost layers, three ounces of
  cerebro-spinal fluid escaped. A second tumour was then found occupying
  the base of the swelling. This was also punctured, more fluid
  escaping. Both sacs were cut away and the wound sewn up. Death
  occurred on the third day, preceded by convulsions, retraction of the
  head and neck, and high fever. The autopsy showed that the fontanelles
  were widely open, the anterior measuring 4 inches from side to side
  and 2¹⁄₂ from before backwards. The bones of the vault were markedly
  thinned. In the subdural space there was a quantity of fluid, and the
  cerebral substance was soft and diffluent, the convolutions flattened,
  and the ventricles distended. There was a broad gap in the occipital
  bone, extending downwards into the foramen magnum, and in this
  situation the cerebellum had bulged backwards into the protruding
  mass. (See Fig. 22).

For _differential diagnosis_, _see_ p. 57.


_Treatment._ In considering the question of treatment, the late
Professor von Bergmann[10] divided the cases into two groups:--

  1. _Inoperable cases._ When associated with premature synostosis and
  microcephaly.

  When associated with hydrocephalus or marked deformity.

  When the tumour is situated below the occipital protuberance.

  2. _Operable cases._ Limited protrusions with none of the above
  defects and disadvantages.

This classification undoubtedly forms a practical basis on which to
estimate the feasibility of operative measures, and it would appear that
sincipital and small occipital cephaloceles are the only cases that come
within the realms of operative treatment. In estimating the possibility
of operation, however, due consideration must be paid to the fact that,
in the very great majority of cases, the tumour tends to increase in
size, the bones become further thinned, the margins of the gap more
everted, and the development of the brain suffers correspondingly.
Again, in spite of the fact that some few cases have survived to adult
age, yet it is the general rule for the patient to die within a few
weeks or months of birth. For desperate ills, corresponding measures
must be undertaken, and in the consideration of the more serious cases
the surgeon should be biased in favour of operation unless the general
condition of the child shows clearly that no success is possible. The
best results have been attained in cases of pure meningocele.


=Operation.= The unhealthy condition of the overlying integument,
especially at the apex of the tumour, prohibits any extensive
preparatory cleansing, this process being carried out for the most part
when the child is under the anæsthetic.

Scalp-flaps are framed from the region of the base of the tumour,
advantage being taken of the more healthy parts. These flaps must be so
sized and framed that accurate approximation and complete covering to
the gap will be attained at the termination of the operation. The flaps
are dissected back to their base. The pedicle of the tumour is defined
and an endeavour made to detach it completely from the margins of the
osseous defect. This is often a matter requiring considerable patience.
The sac of the tumour should then be tapped with trocar and cannula, and
the fluid contents allowed to escape slowly, after which the opening
into the sac is enlarged and the membranes slit up towards the base of
the protrusion.

When dealing with a pure meningocele, the membranous protrusion is cut
away in such a manner that sufficient tissue is left to allow of closure
of the dural gap. This closure can be carried out either by means of a
purse-string suture or by the union of two lateral flaps. In either
case, accurate approximation is essential in order to prevent as far as
possible the further escape of cerebro-spinal fluid.

If the sac should contain an irregular mass of neuroblastic and
mesoblastic tissue, apparently not true cerebral or cerebellar
substance, this material can be dissected from the membranous sac,
ligatured at its base, and freely cut away.

If the sac should contain true brain substance, the possibility of
excision can be raised. In the cerebellar region such measures are
contra-indicated, and the surgeon must remain content with an attempt
at replacing the cerebellar substance within the cranial cavity. This
attempt at reposition will be aided by elevation of the head and,
occasionally, by lumbar puncture. If the protrusion corresponds to a
region which has no known important function, it may be ligatured and
cut away flush with the surface of the gap. Hæmorrhage may be
considerable, but can be controlled by ligature, pressure, and
irrigation with hot water at a temperature between 110 and 115 degrees
Fahrenheit. The degree of shock attendant on the operation may be
severe, necessitating the most complete attention to preliminary,
operative, and post-operative details (see Chap. I).

To _remedy the defect of the bone_ Lyssenkow recommends an osteoplastic
operation, a flap composed of pericranium, together with the external
table of the skull, being framed from the bone above the defect.

The flap is then turned down in such a way that the pericranial surface
faces towards the dura, and the fragment is suspended by the continuity
of the pericranium. He reports 72 cases so treated, with 37 recoveries
and 35 deaths.

König and von Bergmann oppose this osteoplastic operation on the ground
that the extreme thinness of the bone seldom permits of the necessary
splitting off of the external table of the skull, and that, even when
such a course is feasible, the fragment undergoes necrosis.

Transplantation of decalcified and calcined bone, silver and celluloid
plates, have all been tried, with no great amount of success.
Ssamoylenko proposes paraffin and vaseline injections, especially for
the sincipital variety of cephalocele.

When the surrounding bone is of such a nature that it is possible to
form an osteoplastic flap, that course should be adopted. Under other
circumstances, it would appear preferable to postpone any attempt to
close in or protect the gap in the bone in the hope that nature will
remedy the defect in part, the surgeon stepping in at a later date with
one of the measures advocated for the protection of gaps in the skull
(see p. 196).


TRAUMATIC CEPHALOCELES

Many cases have been recorded in which a cephalocele developed after an
injury to the skull. In such conditions it is necessary that a
comminuted or fissured fracture of the vault should be present, that the
underlying dura mater should be torn, and that the adjacent brain
substance should be severely contused or lacerated. Cerebro-spinal fluid
may alone escape through the gap in the skull to the subaponeurotic and
subcutaneous regions, leading to the formation of a _false traumatic
meningocele_. When the brain shares in the outward protrusion the
condition is known as _false traumatic meningo-encephalocele_. This
protrusion of the brain is dependent on the fact that the
injury--necessarily a severe one--leads to considerable brain lesion,
with subsequent œdema and localized or general increase in the
intracranial pressure.

Occasionally, the external accumulation of cerebro-spinal fluid
communicates with one of the horns of the lateral ventricle. A
meningo-encephalocele, having such connexions, is produced in the
following manner:--the protruded brain includes that part of the
cerebral substance which bounds one of the horns of the lateral
ventricle, usually the descending cornu. The ventricular channel becomes
elongated in the outward direction, towards and through the gap in the
skull, whilst the increased intraventricular tension gradually dilates
up the new channel, and, in course of time, still further spreads out
and thins that part of its cerebral boundary which lies external to the
skull deficiency.

There can be no question that after the patient has reached the age of
three years traumatic cephaloceles are of exceedingly rare occurrence.
This special liability in quite young children has been ascribed to the
greater elasticity of the infant skull, and to the supposed greater
adherence of the dura mater. Though these factors may exercise some
influence on the production of the tumour, it seems more probable that
the development of a cephalocele is dependent to a greater degree on the
general vitality of the child. Thus, a blow that produces in the adult a
comminuted or widely fissured fracture of the skull, with laceration of
the dura mater and injury to the underlying brain, frequently leads to a
fatal result, whilst the child often recovers. Again, in the adult, the
force required to produce such a lesion usually suffices to lacerate the
integument. Consequently a compound comminuted fracture of the vault
with hernia cerebri is relatively more common in the adult than in the
infant.

The right side of the head is more frequently affected than the left,
and, of all bones in the skull, the parietal is the one most constantly
involved.


=Symptoms.= During the first few days subsequent to the injury
the child merely suffers from the symptoms common to all severe
head-injuries--concussion and brain irritation. The osseous lesion is
obscured by the presence of a well-marked cephalhæmatoma. After the
lapse of a short time--usually one to two weeks--the partial resolution
of the hæmatoma allows one to observe, for the first time, that a
definite tumour remains. This tumour is irreducible, pulsates freely,
and may be translucent. If the protruding brain substance includes the
precentral region--the motor area--definite weakness or paralysis of the
opposite face and extremities may be observed. Usually, however, no such
symptoms are forthcoming, and the child appears but little the worse for
the accident. Shortly afterwards the tumour becomes more defined in
outline, and careful palpation will reveal the defined margins of an
osseous deficiency. Compression of the protruded mass will often throw
the child into general convulsions, or induce a state of compression
with dilated pupils, slow pulse, and stertorous respiration.
Compression, however, seldom results in any marked diminution in the
size of the tumour. The conditions may remain stationary, but, as a
general rule, the hernial protrusion slowly increases in size and the
child dies in general convulsions, preceded by symptoms of brain
irritation or compression.


=Treatment.= Three courses are available in the treatment of this
condition:--

  1. Expectant treatment, combined with the application of pressure.

  2. Aspiration and puncture.

  3. Free exposure and further treatment according to the conditions
  found.

In the majority of cases the local conditions preclude any attempt at
radical cure--the gap in the skull is large, the margins of the
deficiency are thinned and everted, and the brain enters largely into
the formation of the projecting mass. Furthermore, the dura mater is
torn and in a tag-like condition. Only in the most favourable
cases--when the tumour is small and the gap narrow--can radical
treatment be advocated.

The application of pressure--without previous aspiration--exercises but
little effect on the size of the tumour and, under such treatment, the
danger of brain-compression is always present.

Aspiration with the object of removing the fluid constituents of the
tumour, and thus of reducing its size, has occasionally been followed by
disastrous results. Still, many cases were so treated in the pre-aseptic
days, and the modern methods of cleanliness should allow of better
results. One or more aspirations may be carried out, this treatment to
be followed by the application of steady and uniform pressure,
preferably with the aid of elastic bandages, the degree of compression
depending on the size and constituents of the tumour. The patient must
be watched most carefully, in order to guard against the development of
symptoms pointing to cerebral compression. Irritating injections should
never be used.

One must acknowledge that this mode of treatment has--except in a few
isolated cases--not produced very satisfactory results. Still, since an
open operation is usually out of the question, no other course remains.

The after-history of these cases is not very encouraging. In one of
Weinlecher’s cases the child was living 5 years later, but pulsation was
still present. In Lucas’s case the patient died 21 months later from
meningitis. In Sir T. Smith’s case, pulsation was present 3 years after
the accident, and in Silcock’s there was no marked change for the better
after 11 years. On the other hand, a case reported by Golding Bird
steadily improved, and a second case reported by the same writer gave
every promise of a permanent cure. The two following cases have come
under my own observation:--

  1. A female child, 11 months old, was knocked down by a van, and, on
  admission, a large hæmatoma was seen situated over the right
  temporo-parietal region. The child was semi-comatose, but recovered
  consciousness next day. The hæmatoma softening, a gap in the bone was
  felt, one-third of an inch wide, and extending from the occipital
  bone upwards and inwards to the middle line. The swelling increased in
  size when the child cried. Pulsation was present and translucency was
  obtained. The tumour increased in size for some days, but no untoward
  symptoms developed. For over one month pressure was applied, but
  without much benefit, though the general condition of the child was
  good. The edges of the gap became thickened. The child was then
  removed from the hospital.

  2. A male child fell 19 feet on to his head. He was concussed, and, on
  admission, presented a hæmatoma over the right fronto-parietal region,
  and subconjunctival hæmorrhage in the left orbit. Four days later he
  was apathetic and there was some paresis of the left arm and leg. As
  the hæmatoma became softer, pulsation was noticed over a small area,
  and, in this situation, the swelling increased in size on straining. A
  fracture was detected later, one-third of an inch in diameter, and
  extending across the left frontal bone to the right temporal region.
  Pressure was applied, the tumour steadily decreased in size, and
  eventually the gap was completely closed.

=Synopsis of 38 cases of traumatic cephalocele.=

  _Sex._ Males, 16. Females, 13. Sex not stated, 9.

  _Age at time of accident._

     2 cases at birth.
     9 in the first 6 months.
     9 in the second 6 months.
    14 between 1 and 2 years of age.
     1 between 3 and 10.
     1 between 10 and 15.
     1 between 15 and 20.
     1 between 20 and 30.

  _Region affected._

    Right parietal, 17 cases.
    Left parietal, 4 cases.
    Other bones, right and left, 8 cases.
    Parietal with others, 9 cases.
    Parietal bone involved in 30 out of 38 cases.
    Right side involved in 27 out of 38 cases.

  _Date of appearance of tumour._

     7 cases in the first week.
    11 cases in the second week.
     4 cases in the third week.
     4 cases between 2 and 18 months.
    In the remainder, date uncertain.


=Fractures of the skull resulting from injuries received at or shortly
after birth.= In the consideration of injuries to the skull and brain in
babies the following points should be noted:--

1. The bones of the skull are elastic and pliable, and consequently a
blow may lead to a ‘bending-in’, either temporary or permanent. Slight
depressions may exist without any associated fracture, but all major
depressions are accompanied by a fracture of the bone, especially
evident on examination of the internal table.

2. The fibrous tissue intervening between the component parts of the
vault tends to cause a limitation of the fracture to the particular bone
affected. Downward extension to the base is of infrequent occurrence,
but, when that region is involved, the fracture usually follows the
transbasic lines described in the section dealing with fracture of the
base of the skull (p. 82).

3. The dura is said to be more adherent to the inner table of the skull
than in adults. The relative infrequency in the young of extra-dural
hæmorrhage has been ascribed to this peculiarity. It would appear,
however, more probable that the rarity of such hæmorrhages results from
the bending-in, _without splintering_, of the bone.

4. The brain of the infant is equally--if not more--liable to bruising
and laceration, but the results are far less definite than in adults.
There can be no question that extensive cerebral injury may exist in the
child without leading to the development of any definite localizing
symptoms.


FRACTURES OF THE VAULT


(_a_) =Depressed fractures.= Depressed fractures either result from
injury received during the birth of the child--whether from forceps
delivery or from the pressure exerted on the head by a contracted
pelvis--or from blows received shortly after birth.

[Illustration: FIG. 23. A DEPRESSED BIRTH-FRACTURE.]

The depression, varying greatly in depth and extent, may be situated
over any part of the skull, but commonly involves the fronto-parietal
region. It is often obscured in the early stages by the presence of an
overlying hæmatoma, the condition perhaps only being discovered after
the absorption of the blood-clot. In many cases no symptoms result,
partly owing to the shallowness of the depression and partly due to the
situation of the lesion over one of the so-called ‘silent’ areas of the
brain. Under other circumstances the child may evidence the general
increase in the intracranial pressure by cyanosis, difficulty in
respiration, unconsciousness, and slow pulse. The anterior fontanelle
will be tense, and pulsation will be absent or greatly diminished--a
feature of the greatest diagnostic value. Localizing symptoms ensue when
an extensive depression is situated over the motor area, the extremities
of the opposite side being flaccid, or evidencing irritation by
twitchings and convulsions. The ready response of the infant to cortical
irritation frequently results in the early transformation of local
twitchings into general convulsions.


=Course and treatment.= It is often stated that these depressed
fractures remedy themselves in the course of time, the development of
the underlying cortex curing the depression by the outward leverage
exerted. In the minor degrees of depression there may be some chance of
such spontaneous cure. I am, however, entirely opposed to the view that
spontaneous cure is the rule, and there can be no question that the more
severe types of depression remain as permanent defects unless surgical
remedies are adopted. Furthermore, even if the deformity should cure
itself in time, the intermediate dangers are not to be disregarded,
for, during the process of spontaneous cure, there is a decided
liability for the depressed cortex to lag behind in the process of
development, or to undergo degenerative changes as the result of the
pressure exerted--with disastrous results on the parts supplied by the
region compressed. Mental deficiency, paralyses, and contractures will
result, and there is every reason to believe that some cases of
infantile paralysis are dependent on this lesion.

The following case, recently under my care, adds further proof to the
statement that spontaneous cure is usually out of the question:--

  The child, 10 weeks old, was admitted with a depressed fracture over
  the parieto-frontal region, oval in shape, and about 3¹⁄₂ inches in
  its long antero-posterior diameter. The centre of the depression lay
  about 1¹⁄₂ inches below a normal surface. The injury was produced at
  birth (contracted pelvis), and frequent convulsions were observed
  during the first few days of life. The fits then ceased, but the
  depression became, if anything, more marked day by day. The child was
  then brought up to see me. The depression was exposed by a suitable
  scalp-flap and a small trephine hole made immediately posterior to the
  depression. The dura mater was stripped away from the under surface of
  the bone and every effort made to remedy the depression. No impression
  was thus made on the defect. The whole depressed area was then cut out
  with a pair of scissors, the segment removed, wrapped up in a piece of
  gauze, and forcibly manipulated in the hope that the depression could
  be overcome and the segment placed back in the normal position. This
  attempt was also greeted with failure. The segment was then placed
  back in the inverted position, the dural surface external and vice
  versa. The segment required some trimming with the scissors before it
  fitted accurately in position. The scalp-flap was then replaced. The
  child suffered but very slightly from the operation, firm union was
  present in two weeks, and, six months later, examination of the skull
  showed that the two sides were absolutely symmetrical.

  It should be noted that, although the child was only 10 weeks old, and
  in spite of the fact that the depression was fully exposed, it was
  quite impossible to lever up the depressed bone. This hardly coincides
  with the views of those who maintain that birth-depressions undergo
  spontaneous cure.

Taking all these facts into consideration, it would appear advisable to
adopt the following course:--slight depressions, situated in the region
of ‘silent’ areas of the brain, may be left for one or two weeks, and,
in the event of failure at spontaneous cure, the depression must be
elevated. In all the more serious cases, whether associated with
symptoms of brain-pressure or not, surgical interference is imperative.

[Illustration: A

B

FIG. 24. A CASE OF DEPRESSED BIRTH-FRACTURE. A, Before operation; B,
After operation. (For further description, see text.)]


=Operation.= The baby would be well wrapped up and, after shaving and
cleansing of the scalp, the scalp-tourniquet applied. Babies stand these
operations exceedingly well so long as hæmorrhage is but slight. A
scalp-flap is turned down and a small trephine (¹⁄₂-inch diameter)
applied immediately to one side of the depression, the trephine circle
including the outer margin of the depressed area. The dura is stripped
away and a flat periosteal elevator introduced so that its apex
corresponds to the apex of the depression. An attempt is then made to
lever the depressed area in the outward direction. If that result be
attained, well and good. The flap is replaced and dressings applied. In
many cases, however, the elevated region promptly assumes its original
depressed position as soon as the elevator is removed, and, in other
cases, all attempts at rectification of the deformity are of no avail.
Under these circumstances, it is advisable to carry out the method
advocated by Nicholl--adopted in the case described above--the whole of
the depressed area being cut out with blunt-pointed scissors, reduced to
a more normal curvature by manipulation between layers of gauze, and
replaced in the inverted position, the original dural surface becoming
now external. This inversion is requisite, as it is usually quite
impossible--even under considerable pressure--to reduce the depression
to a permanently satisfactory degree.

Nicholl reports on 23 cases, the ages of the patients varying from 3
weeks to 8 years. The first 13 cases were treated by elevation. The
results obtained were most unsatisfactory, complete reduction of the
deformity seldom being attained, whilst recurrence, of a greater or
lesser degree, was the rule.

In the last 10 cases the inversion method was carried out, with, in all
cases, satisfactory results. Bony union was present in 10 days.

Four cases of depressed birth-fractures have come under my own care. In
two cases the depression was elevated--in both cases with considerable
difficulty--whilst in the other two cases, after failure of leverage,
Nicholl’s method was carried out, in both cases with eminently
satisfactory results.

(_b_) =Fissured fractures.= Fissured fractures are especially prone to
involve the parietal bone, and, in their direction, to follow the lines
of ossification. Thus, in the case of the parietal bone, the fissures
will radiate from the parietal prominence. There is also a certain
tendency for the fracture to remain limited to the particular bone
affected.

The presence and extent of the fracture is commonly obscured by the
overlying hæmatoma, which is either subpericranial or subaponeurotic. On
the other hand, the hæmatoma may, from its size and shape, supply
evidence as to the nature of the underlying lesion. Thus, when confined
to the parietal bone, it may be inferred that the fracture is also
limited to that region. Again, when linear, the presumption is that the
fracture is of a similar nature. A definite diagnosis may be impossible
without aspiration or till after absorption of the hæmatoma. The fissure
will then be found to vary in extent from a mere crack in the bone to a
wide gap as broad or broader than the width of the finger. In a case
recently under my care the fissure, over half an inch in breadth,
extended from the vertex to the base, whilst throughout the whole extent
of the gap pulsation was readily obtained.

Fissured fractures in the very young possess another point of interest
in that the cleft often tends to increase, this being notably the case
when the fracture is associated with injury to underlying dura and
brain. The local and general increase of intracranial pressure not only
widens the gap, but also leads to thinning and eversion of the margins
of the deficiency with possible herniation of brain-matter--traumatic
cephalocele.


=Symptoms.= In many cases--in spite of the severity of the lesion--there
are no symptoms, the child appearing but little the worse for the
accident. In most cases, however, the child evidences symptoms of
brain-concussion, irritation, or compression, for which conditions
reference should be made to the sections dealing with those subjects.

It should be noted, however, that the anterior fontanelle supplies
evidence as to increase or decrease of intracranial pressure. In
concussion the fontanelle is depressed, in compression it is tense and
pulsation is absent or diminished. Irritation of the brain is evidenced
by irritability and general convulsions.


=Treatment.= In the absence of symptoms, or when the fracture is
associated with concussion or irritation, operative measures are
contra-indicated, the patient being treated after the general principles
laid down for those conditions.

When associated with symptoms of brain-compression, exploration is
almost always advisable, the scalp-tourniquet being applied and the
injured region exposed by a suitable scalp-flap. Depressed bone is
elevated, or the trephine applied so as to fully expose the underlying
dura mater. A bulging, non-pulsatile, and plum-coloured membrane points
to the existence of a subdural hæmatoma. The membrane is then incised
and the clot evacuated. Whenever possible the dura mater should be sewn
up and the scalp-flap replaced without drainage.

Operative measures are also indicated when a linear fracture gapes
widely--especially when the gap shows a tendency to increase in width.
The steps of such an operation are as follows:--

1. Expose the fracture throughout its whole length.

2. Cut away all pericranium or fibrous tissue that intervenes between
the margins of the cleft.

3. Separate the dura mater from the bone on either side of the cleft for
a distance of about ¹⁄₂ inch, at the same time sewing up any rents in
the membrane.

4. Bore a few holes through the skull--using an ordinary bradawl--on
either side of the cleft, the holes being placed about ¹⁄₂ inch apart.

5. Approximate and lace the margins of the cleft by means of fine silver
wire or strong catgut.

6. Sew up the flap without drainage.


BIRTH-HÆMORRHAGES


=Extracranial hæmorrhages.= As the result of injury sustained during
protracted labour, hæmatomata may develop beneath the aponeurosis of the
occipito-frontalis or underneath the pericranium, the latter being the
more common situation. The right side of the head is the more frequently
involved, and the parietal region is the part usually affected.
Occasionally these hæmatomata are bilateral and symmetrical.

The two varieties of cephalhæmatoma--subaponeurotic and
subpericranial--possess certain peculiarities that aid materially in
their differential diagnosis.


_Subaponeurotic hæmatomata._ The blood, though spreading widely
throughout the subaponeurotic space, tends to gravitate towards the
lower confines of that space, and, from the position assumed by the
patient, is most evident in the occipital region. The presence of the
blood is evidenced by œdema, doughiness, and ecchymosis.


_Subpericranial hæmatomata._ The blood is confined to the region of the
particular bone affected, usually the right parietal bone. This is due
to the fact that the pericranium blends at the margins of the bone with
the tissue intervening between that bone and the neighbouring parts of
the skull.

Subpericranial hæmatomata present further peculiarities. The tumour is
usually more or less circular in outline, and fluctuates freely. It may
arise immediately after the birth of the child, but, more commonly, some
two or three days elapse before attention is drawn to its existence.
Within a few days clotting occurs at the periphery of the hæmatoma with
the formation of a circumferential ridge. The central portion of the
clot remains soft but tense, so much so that firm pressure is required
before the examining finger is enabled to feel the underlying bone.
These cephalhæmatomata are not infrequently mistaken for depressed
fractures, but no difficulty should be experienced if the existence of
the circumferential ridge be appreciated and if the underlying bone can
be felt at the centre of the tumour. In cases of doubt the blood should
be drawn off by aspiration and the swelling again examined.

For _differential diagnosis_, see p. 57.


=Treatment.= The less extensive hæmatomata require no active surgical
treatment, the absorption of the clot being aided by protection of the
part and by cooling lotions.

Similar expectant treatment is generally advised with regard to the
extensive subpericranial hæmatomata, but as infection of the clot may
take place, and as its resolution invariably requires a considerable
period of time--often many weeks--more active measures can be adopted.
The region of the hæmatoma is carefully shaved and cleansed, and, under
local anæsthesia, a small incision made through the scalp, the clot
squeezed out, and firm pressure applied. Under this form of treatment
the patient is well within a few days.


=Intracranial birth-hæmorrhages.= Attention was first drawn to the
question of intracranial birth-hæmorrhages by Little, who showed that a
history of difficult labour could be obtained in a large percentage of
cases in which children in after-life suffered from uni- or bilateral
spastic paraplegia; hence the name, ‘Little’s disease’ or birth palsy.
Further information was supplied by Sarah MacNutt, and the whole
question was fully investigated by Harvey Cushing.

In all cases a history of difficult and protracted labour can be
obtained, with considerable post-partum respiratory difficulties, the
child being described as ‘blue in the face’ for some hours after birth.

The stress and strain which the advancing head undergoes, and the
consequent moulding and overlapping of the various segments of the
skull, exposes the brain to great alterations of pressure, and throws
considerable tension on the intracranial veins. It is, in fact, rather
surprising that birth-hæmorrhages are not more common.

The hæmorrhages may be wholly within the meshes of the pia-arachnoid
system, but, in the great majority of cases, the lesion is more serious,
and the extravasation comes to lie within the subdural space.

Occasionally the bleeding takes place beneath the tentorium cerebelli,
the blood-clot lying in relation to the pons and medulla. Such
hæmorrhages are said to be observed only in vertex presentations. The
more common supratentorial hæmorrhages--usually resulting from difficult
breech presentations--either remain more or less localized to a certain
region of the cortex, or become widely diffused over the surface and
base of the brain.

It is probable that Cushing is correct in his observations with respect
to the source of these supratentorial hæmorrhages. He states that the
blood is derived from one or more radicles of the superior longitudinal
sinus, especially from those veins which, in their upward passage in the
sulci of the brain, leave their cerebral beds for a short and
comparatively unprotected course, immediately previous to their entry
into the lacunæ laterales of the superior longitudinal sinus.

In addition, he points to the very important fact that the localized
hæmorrhages are commonly situated in relation to the mid-cerebral
cortex, close to the sinus, and on one or both sides of the falx
cerebri. In addition, therefore, to the symptoms of general cerebral
compression, certain definite localizing symptoms are to be observed,
these being in direct proportion to the size of the clot.

In an analysis of 74 autopsies on infants still-born or dying within the
first few days, Archibald[11] found ‘intrameningeal’ hæmorrhage in 32,
in 19 of which it was of considerable extent: and in 5 others there was
extra-dural hæmorrhage. In only two or three was effused blood found
within the cerebral cortex. The importance of these facts from a
surgical point of view cannot be over-estimated.

[Illustration: FIG. 25. DIAGRAM TO ILLUSTRATE THE EFFECTS AND POSITION
OF A BIRTH-HÆMORRHAGE. _sc._, Scalp; _b._, Bone; _d.m._, Dura mater;
_br._, Brain; _s.l.s._, Superior longitudinal sinus; _c.v._¹, The
protected part of a superficial cerebral vein; _c.v._², The unprotected
part of a superficial cerebral vein; _c._, The subdural clot, exercising
pressure on (1) the cortical leg arm, (2) the arm area, and (3) the face
area.]


=Symptoms.= Besides the history of protracted labour and the ‘blue’
asphyxiated appearance of the baby, other evidence is to hand with
respect to both general and local increase of brain-pressure.

The _general_ increase is evidenced first and foremost by the bulging
and non-pulsatile anterior fontanelle. The fontanelle may be regarded as
an index of intracranial pressure. The margins of the fontanelle are
outlined with some difficulty, and, owing to the free communication
between the intra- and extra-cranial venous systems, the scalp-veins are
unduly prominent. The general condition of the child varies according to
rise of intracranial pressure. In the more serious cases it may be
impossible to arouse the patient: in the slighter hæmorrhages the child
may appear but little the worse, with the exception, perhaps, of being
rather more irritable than usual.

The effect of the pressure on the medullary centres is shown by
respiratory difficulties--irregularities of rhythm, &c.--some
retardation in pulse-rate, and increase in blood-pressure. The reflexes
are increased and the child is readily thrown into general convulsions.

The effect of the _localized_ pressure on the upper Rolandic centres
seldom becomes evident till after the lapse of a few days--and often
after a longer period--when muscular weakness, twitchings, rigidity, or
paralysis--more especially of the contralateral lower extremity--becomes
apparent. The mother often draws attention to the fact that the child
does not move one of its legs properly.

When the extravasation is extensive, spreading downwards over other
motor areas, the upper extremities and even the face may be involved.

When a small hæmorrhage is present, situated on either side of the falx
cerebri, both lower extremities suffer and diplegia results.

In some cases, chemosis of the conjunction, œdema of the lids, and
proptosis have been observed. In any case an ophthalmoscopic examination
should be carried out. Frequently some fullness of the retinal veins and
diminution in the calibre of the arteries supply confirmatory evidence.

In the event of doubt in diagnosis, lumbar puncture should be carried
out. It should be noted, however, that although the positive evidence of
free blood corpuscles points to subdural hæmorrhage, yet that absence of
blood in the fluid withdrawn does not exclude the possibility of a
localized and more or less encapsulated hæmorrhage. In the event of
failure at recognition of the serious lesion present, disastrous results
will ensue--monoplegia, diplegia, hemiplegia, epilepsy, and idiocy.


=Treatment.= The age of the patient must not be allowed to weigh in the
balance against operative treatment, for, if due precautions be taken,
the new-born child stands operation well. Cushing points out that ‘the
possibilities of surgical relief are limited to the first week or two
after the hæmorrhage has occurred, for old cortical scars can neither be
helped by medicine nor by the scalpel’.

The clot can be exposed by craniectomy or by craniotomy. The latter
operation results in a more complete exposure, but the shock is
undoubtedly more severe. Exposure by craniotomy is advocated by Cushing,
and carried out in the following manner: ‘An omega-shaped incision just
within the outer margin of the parietal bone is carried down to the bone
through the scalp and pericranium, and the latter is scraped away so as
to expose the thin serrated edge of the parietal bone. Under this a
blunt dissector is passed, so that the edge of the bone is tilted up,
and then, with a proper cutting instrument (strong blunt-pointed
scissors suffice), the bone is incised in a line conforming with the
skin incision 1 centimetre or more within the parietal margin. The
parietal bone is then broken across at its base. The dura is opened by a
curved incision some distance within the bony margin, and the
superficial clot broken away or lifted off in fragments, or irrigated
away with a gentle stream of warm saline solution. The dura should be
accurately sutured, the bone replaced, and the skin closed with suture.’

He reports on 9 cases so treated, with 4 recoveries, apparently complete
and permanent. The fatal cases were all associated with extensive
extravasation over the entire hemisphere. In 3 cases bilateral exposure
was necessitated.

Taking, however, the question into more general consideration, it would
appear that equally satisfactory results can be obtained, with a lesser
degree of operative danger, by carrying out craniectomy in the manner
described in the treatment of ‘traumatic subdural hæmorrhage’ (see p.
156).


DERMOIDS

Dermoids, in this region of the body, are almost invariably situated in
the middle line between nasion and inion, though cases have been
described in which congenital tumours, dermoid-like in nature, were
situated over the mastoid process and in other regions.

They occur with the greatest frequency over the anterior fontanelle and
in the region of the external occipital protuberance. In the latter
situation they are specially prone to possess those deep attachments to
the dura mater which are further alluded to below. In the great majority
of cases careful examination will show that the tumour occupies a
depression in the bone, saucer-like in nature, in which the tumour
rests. They are seldom freely movable, and are often markedly fixed,
being either attached to the pericranium or to deeper structures. They
are not attached to the overlying skin. The tumour is irreducible, and
pulsation is absent except in those rare cases where, in the presence of
a wide gap in the skull, transmitted pulsation may be obtained.

On careful dissection it may be found that the tumour communicates, by
means of a small hole in the skull, with the underlying membranes. In
more exceptional cases a wide gap in the skull may be found by means of
which the dermoid obtains extensive connexion with the dura mater and
even with the brain. In rare cases the dermoid may be pedunculated.

Bland Sutton drew attention to this frequent connexion between the
dermoid and the membranes of the brain, showing further that the entire
tumour may lie on the inner side of the occipital bone.

The following account affords further information as to the nature and
origin of cephalic dermoids.

  ‘Morphologically considered, the bony framework of the skull is an
  additional element to the primitive cranium which is represented by
  the dura mater, and the term extra-cranial should be applied to all
  tissues outside the dura mater. Early in embryological life the dura
  mater and skin are in contact; gradually the base and portions of the
  side wall of the membranous cranium chondrify, thus separating the
  skin from the dura mater. In the vault of the skull, bone developes
  between the dura mater and its cutaneous cap, but the skin and dura
  mater remain in contact along the various sutures even for a year or
  more after birth. This relation persists longest in the region of the
  anterior fontanelle and the neighbourhood of the inion. Should the
  skin be imperfectly separated, or a portion remain persistently
  adherent to the dura mater, it would act precisely as a tumour germ
  and give rise to a dermoid. Such a tumour may retain its original
  attachment to the dura mater, and its pedicle become surrounded by
  bone; the dermoid would lie outside the bone but be lodged in a
  depression on the surface, with an aperture transmitting its pedicle.
  On the other hand, the tumour may become separated from the skin by
  bone; it would then project on the inner surface or between the layers
  of the dura mater. If this view of the origin of dermoids be accepted,
  we must modify our teaching and say that the depressions in which
  dermoids of the cranium are lodged arise as imperfections in the
  developmental process, and are not due to absorption induced by
  pressure; further, the fibrous connexion of such dermoids with the
  dura mater is primary, not accidental.’[12]


=Treatment.= When of inconsiderable size, and when intracranial
connexions are absent, of doubtful existence, or of slight extent, the
sooner the tumour is removed the better. The dura mater should not be
opened unless absolutely necessary, in which case it should be carefully
sewn up and the scalp-flap replaced without drainage.

When possessing deep and extensive connexions, careful dissection may
still allow of the complete removal of the dermoid. It is impossible to
foretell with certainty whether it is possible to remove the tumour
until its basal portion is exposed. The operation may be a formidable
one.

SOME POINTS IN THE DIFFERENTIAL DIAGNOSIS BETWEEN CEPHALOCELES,
DERMOIDS, AND CEPHALHÆMATOMATA

  ----------------------+------------------------+----------------------
      _Cephaloceles     |      _Dermoids._       |  _Cephalhæmatomata._
      (congenital)._    |                        |
  ----------------------+------------------------+----------------------
  Present at birth.     |Present at birth.       |Usually appears
                        |                        |after birth.
                        |                        |
  In middle line,       |In middle line,         |Always to one side of
  especially over       |especially over anterior|the middle line, and
  occiput and base of   |fontanelle.             |usually over the
  nose.                 |                        |parietal bone.
                        |                        |
  Firm or fluctuating.  |Firm.                   |Fluctuation over
                        |                        |central part only.
                        |                        |
  Perhaps translucent.  |Not translucent.        |Not translucent.
                        |                        |
  Perhaps pulsates.     |Does not pulsate.       |Does not pulsate.
                        |                        |
  Perhaps reducible, in |Irreducible.            |Very slightly, if at
  whole or in part.     |                        |all.
                        |                        |
  Perhaps swells up     |No alteration.          |Very slightly, if at
  on straining.         |                        |all.
                        |                        |
  Perhaps associated    |No cerebral symptoms.   |No cerebral symptoms.
  with cerebral         |                        |
  symptoms.             |                        |
                        |                        |
  Gap in skull felt.    |Depression in bone      |Deceptive raised
                        |common, actual gap      |margin, no actual
                        |comparatively rare.     |central depression.
  ----------------------+------------------------+----------------------


HYDROCEPHALUS

The conditions that lead up to internal hydrocephalus are classified by
Parkes Weber[13] in the following manner:--

1. ‘Cases secondary to and part of the phenomena of tuberculous or any
suppurative meningitis, comparable to pleural effusions due to
tuberculous or any septic invasions of the pleura.

2. Cases resulting from the presence of tumours, &c., analogous to the
pleuritic effusions accompanying tumours, &c., situated close to or
involving the pleura.

3. Ordinary infantile or congenital hydrocephalus, which is, in some
cases at least, due to intra-uterine meningitis.

4. Internal hydrocephalus supervening on the epidemic or sporadic type
of posterior basic non-suppurative meningitis.

6. Simple idiopathic internal hydrocephalus of adults or older children
due to serous ependymitis or ventricular meningitis.

7. Traumatic cases.’

This classification possibly includes all the various grades and degrees
of internal hydrocephalus, but for all practical purposes the cases may
be grouped into two classes, congenital and acquired, both of which may
be either acute or chronic.


=Congenital internal hydrocephalus.= The condition may be recognized
soon after the birth of the child, or the enlargement of the head may
only become apparent some weeks or months later. The slow development
and the insidious nature of the enlargement, as observed in many cases,
may lead to some confusion between the late congenital and the early
acquired varieties. However, the absence of any symptoms pointing to
meningeal inflammation between the time of the birth of the child and
the hydrocephalic development usually allows of correct classification.

It is doubtful whether congenital internal hydrocephalus can be ascribed
to malformation of the inter-ventricular channels and occlusion of the
passages by means of which the cerebro-spinal fluid escapes into the
cerebral subarachnoid space, or whether the development is dependent on
hypersecretion from the ependyma and choroid plexuses. Virchow showed
that occasionally there was an actual formation of small grey-red
masses, about the size of a hemp-seed or cherry, in the walls of the
ventricles, but other authorities deny the existence of such changes,
and consider that the hydrocephalic condition is entirely dependent on
congenital malformation.

It would, however, seem more probable that we have to deal with two
distinct varieties of congenital internal hydrocephalus, one resulting
from intra-uterine ependymal inflammation (? syphilitic), the other
dependent on congenital malformations, especially in the region of the
fourth ventricle, where the foramina of Majendie, Key, and Retzius are
regarded as permitting the outward escape of the fluid secreted from the
lining membrane and choroid plexuses of the ventricles.


=Acquired hydrocephalus.= Acquired hydrocephalus, whether acute or
chronic, presents certain antecedents or associations which enable us to
have a more clear idea as to the pathological conditions present.

In the majority of cases it is secondary to basic meningitis which,
whether tuberculous or not, results in matting of membranes and in the
development of adhesions. The normal flow of cerebro-spinal fluid from
the ventricular to the cerebral subarachnoid spaces is thus impeded.

Similar interference to the flow of cerebro-spinal fluid may be caused
by the growth of a tumour, especially those which originate in the
subtentorial region.


=Progress of the case.= Whether the progress of the case be acute or
chronic, the ultimate results are much the same. The fluid in the
ventricular spaces may be increased up to 1,000 c.c. or more, pressure
effects being exerted on the surrounding parts, with the following
results:--

_A._ The soft cerebral substance is slowly but surely compressed, with
the result that the sulci on the surface of the brain are more or less
obliterated, distinction between the white and grey matter may be lost,
the ventricular spaces are enormously dilated, and, in the most marked
cases, a mere shell of brain may intervene between the ventricles and
the surface of the brain.

This cerebral compression results in the development of two main groups
of symptoms, those referable to the general increase in the
intraventricular pressure and those due to regional compression.

The more general results are headache, vomiting, optic neuritis and
atrophy, slow pulse-rate, somnolence, and coma. The temperature is
variable, more commonly rising during the more acute stages of the
disease, and falling to normal or subnormal during the quiescent
periods.

Localizing features are to be found in squints, inequality of pupils,
retraction of the head and neck, dyspnœa, and dysphagia, whilst
compression of the cortical motor centres is evidenced by twitchings,
convulsions, and spasticity of the limbs. General convulsions are by no
means uncommon. Remissions and intermissions of both local and general
symptoms are frequently observed, paralyses, for example, fluctuating in
depth and character.

_B._ The bones comprising the vault of the skull become greatly thinned
and widely separated from one another, the fontanelles enlarged, and the
sutures unduly prominent. The head becomes enlarged in all directions,
and its increased weight renders the child incapable of retaining
postural control, the head being top-heavy and falling about in all
directions.

The bones of the base share in the deformity. The pressure exerted on
the orbital plates of the frontal bone force the globe in the downward
direction in such a manner that the infra-corneal sclerotic is obscured
by the lower lid, whilst the supra-corneal portion is unduly prominent.
The bony eminences in the region of the sella turcica are diminished in
size, the middle fossa of the skull flattened from side to side, and the
posterior fossa from before backwards. In such cases the skull assumes
an almost dolicocephalic appearance. In any case, the disproportion
between the enlarged skull and diminutive face is a marked feature.[14]

The scalp becomes stretched, hairs are sparse and brittle, and the veins
dilated.


=Treatment.= _Indications for operation._ The results obtained by
operation for internal hydrocephalus are not sufficiently encouraging to
enable the surgeon to urge immediate operative treatment.[15] Still, it
is perfectly clear that he cannot possibly carry out surgical treatment
with benefit to the patient if the ventricular distension is allowed to
progress to such a degree that marked cortical flattening and
degeneration occurs. No fixed probationary period can be laid down as a
guide, each case must be judged on its own merits. Special attention
should be paid, however, to the disks and lower extremities. Any
suggestion of optic neuritis or spasticity should be regarded as
urgently demanding operative interference.


_Lumbar puncture_ cannot be expected to confer other than temporary
benefit even under the most favourable circumstances, whilst, in the
event of interference in the normal communication between the
ventricular and cerebro-spinal spaces, no relief can be anticipated.
Connal recommends that lumbar puncture should be carried out daily, or
twice daily, over extended periods of time. This operation, however, is
by no means devoid of danger, and the results obtained by such treatment
are not at all satisfactory.


=Operation.= Operations are carried out (_a_) with the object of
withdrawing fluid from the distended ventricular cavities (ventricular
puncture), and (_b_) to establish a communication, or short-circuit,
between the ventricular space and other spaces (ventricular drainage).


_Ventricular puncture._ This operation may be carried out through the
anterior fontanelle, through the frontal bone, or over the descending
cornu of the lateral ventricle.


_Through the anterior fontanelle._ The region of the fontanelle is
shaved and cleansed in the usual manner, after which the surrounding
parts are cut off from the field of operation by a large sheet of gauze
or lint, in which a hole is cut sufficing to allow of exposure of the
site of election for puncture.

The patient should be in the recumbent position, the head well towards
the end of the table. The operation is performed without an anæsthetic
or under local anæsthesia. A site is chosen at the outer angle of the
fontanelle, about 1 inch away from the median antero-posterior line,
thus avoiding all possibility of injuring the superior longitudinal
venous sinus. The trocar and cannula, of small size, is passed directly
inwards, towards the base of the skull, for a distance of not more than
2 inches. The trocar is withdrawn and the fluid allowed to escape
slowly. If the cerebro-spinal fluid escapes at high pressure, the flow
should be regulated by the finger placed over the mouth of the cannula,
and, in any case, it is inadvisable to allow of the withdrawal of more
than 50 c.c. (approximately 1¹⁄₂ ounces) at one sitting. The cannula is
withdrawn and the site of tapping covered with collodion gauze. Even
when adopting all precautions the operation is not without danger, and,
added to this, is the fact that few surgeons care about introducing an
instrument blindly into the cerebral cortex--the risk of puncturing one
of the distended superficial cerebral veins is sufficiently obvious.


_Through the frontal bone._ Tillmanns, in recommending this procedure,
states that ‘the needle should be inserted about 2 centimetres from the
central line and 3 centimetres from the precentral sulcus. You strike
the ventricle at a depth of from 3 to 5 centimetres’. He claims that
this method leads to satisfactory results. It is open, however, to all
the objections of puncture through the fontanelle.


_Over the descending cornu of the lateral ventricle._ This operation is
strongly recommended by Keen on the ground that excellent drainage is
supplied. A point is mapped out on the skull which lies 1¹⁄₄ inches
behind the external auditory meatus and the same distance above Reid’s
base-line. If the postero-lateral fontanelle be open a small trocar and
cannula may be introduced at the upper angle of the space--thus avoiding
the lateral sinus--and passed inwards in a direction towards the summit
of the opposite ear. If the fontanelle be closed, a scalp-flap is framed
and a bone-disk removed with a ¹⁄₄¹⁄₂ inch diameter trephine. The dura
should not be opened. The evacuating instrument is then introduced
through the membrane in the same direction as before. In either case it
should not be passed for a greater distance than 1¹⁄₂ inches, and, in
all cases, the exploration should be of a progressive nature, that is to
say, the trocar should be withdrawn once for each ¹⁄₂ inch of brain
substance perforated. The escape of cerebro-spinal fluid must be
regulated in the manner previously described.

If trephining has been necessitated, the bone-disk is not replaced, thus
allowing of subsequent tappings through the trephine-hole, this gap now
taking the place of a patent postero-lateral fontanelle.

Keen’s method of ventricular puncture presents many advantages over
other methods, though still open to the objection that the actual
central puncture is done blindly.


=Ventricular-subdural drainage.= A point is mapped out on the scalp
which corresponds to the surface-marking of the descending horn of the
lateral ventricle (see p. 3), and, with this point as a guide, a
scalp-flap is framed, the base of which lies immediately below the
indicated spot whilst its convexity is situated between 1¹⁄₂ and 2
inches above. This flap should not include the pericranium. The flap is
turned down to its base, the pericranium stripped aside and a disk of
bone removed, at the upper part of the exposed bone, with a ¹⁄₄ or ¹⁄₂
inch diameter trephine. The bone is usually very thin.

[Illustration: A

B

FIG. 26. DIAGRAMMATIC REPRESENTATION OF THE AUTHOR’S OPERATION FOR
HYDROCEPHALUS INTERNUS. A. The osteoplastic exposure of the brain (A,
The bone; B, Upper two-thirds of trephine hole; C, Dura mater; D, The
four dural flaps; E, Site of brain perforation; F, The brain; G, Line of
fracture of bone-flap; H, The bone-flap; I, The Scalp; J, Lower third of
trephine hole). B. Ventriculo-subdural drainage (_s._, The scalp; _b._,
The bone; _d._, The dura mater; _v._, The lateral ventricle; _t._, The
drainage medium between the ventricular cavity and the subdural space;
_s.l.s._, Superior longitudinal sinus; _f.c._, Falx cerebri).]

When this disk is removed, the dura is separated from the bone, and,
with the aid of a strong pair of scissors, the bone is cut in such a
manner as to form a bone-flap, the margins of which lie well within
those of the scalp-flap (see Fig. 26). This flap is broken across at its
base, turned down, and covered with gauze.

At the lower portion of the exposed dura mater, a crucial incision is
made through the dura mater and a blunt-pointed trocar and cannula
introduced at the centre of the exposed brain, all visible vessels being
avoided. The diagnosis is now confirmed--by the withdrawal of the trocar
and the escape of cerebro-spinal fluid.

[Illustration: FIG. 27. THE CONVERSION OF HYDROCEPHALUS INTERNUS INTO
CEPHALOCELE.]

By the introduction of a bundle of horsehair or catgut, passed through
the cannula so as to project into the ventricular cavity, and, after the
withdrawal of the cannula, tucked, with respect to the proximal ends,
into the subdural, extra-dural, or subaponeurotic spaces, it is obvious
that drainage may be established between the ventricles and the other
regions. Experience showed, however, that drainage into the
subaponeurotic space usually converted the condition of hydrocephalus
into one of cephalocele (see Fig. 27), the fluid collecting as a
localized fluid tumour over the region of exploration, whilst
extra-dural drains did not permit of sufficiently rapid reabsorption of
fluid. Subdural drainage gave the best results, the cerebro-spinal fluid
being brought into relation with the pia-arachnoid meshwork of vessels.
It would, of course, be infinitely preferable if the ventricular fluid
could be brought into direct relation with the veins of the
_subarachnoid_ space, for the cerebro-spinal tension and venous pressure
are equal, and all excess of cerebro-spinal fluid would be absorbed as
soon as it is formed. This course is, however, impossible to carry out.
We have, therefore, to rest content with less direct contact, drainage
into the _subdural_ space. This ventricular-subdural drainage, as
obtained by horsehair, catgut, and silk, apparently leads to but
temporary benefit, probably owing to falling together of the brain
substance and obliteration of the adventitious passage.

Silver tubes and bone tubes have been utilized, but the results are
sometimes disappointing. In one of my recent cases the two halves of a
bone tube were utilized. The tube was cut across in an oblique manner at
about its centre, the two parts set at right angles to one another and
sewn together with silk. One arm is introduced into the ventricle, the
other tucked underneath the dura mater. The child improved considerably,
but the method is not altogether satisfactory and by no means easy of
application. In another case I utilized strands of silver wire. The
depth of brain-tissue necessary to reach the ventricular cavity was
measured, and two or three strands of wire introduced so as to project
well into that space, then steadied with forceps whilst the proximal
ends were bent at right angles to the surface of the brain and tucked
underneath the dura mater. The method was unsatisfactory.

Tubular drainage is not essential, for the fluid escapes from the
ventricle as much alongside the tube as through its lumen. Still, I
believe that tubular drainage is preferable to other methods, and,
realizing the difficulty of introducing a right-angled tube--one arm to
project into the ventricle, the other to lie beneath the dura
mater--Messrs. Arnold & Son are now making for me small and light
right-angled silver tubes so constructed that each limb can be inserted
independently, after which they can be locked together. This method
appears to overcome many of the difficulties previously encountered. The
tube is inserted after the formation of the osteoplastic flap, as
described above. The four dural flaps are then united, preferably by
cross union of their apices, the bone-flap is replaced, and the
scalp-flap sewn accurately into position. Collodion gauze, applied to
the wound, aids in the prevention of cerebro-spinal escape.

The scalp and bone-flaps are framed, and the dural incision carried out
low down, so as to make the opening to the brain as valvular as
possible. All these precautions are taken to avoid leakage of
cerebro-spinal fluid, a most troublesome complication--adding to the
risk of infection and often resulting in an acute eczematous condition
of the surrounding skin.

By this method it is hoped that a permanent fistulous communication will
be formed between the lateral ventricle and the subdural space.


=Ventriculo-abdominal drainage.= The following method of drainage has
been devised by Cushing: ‘It having been established that the ventricle
can be emptied by the lumbar route, and that the withdrawal of fluid is
not prejudicial to the child’s well-being, the following procedure is
carried out. A laparotomy is performed; the posterior layer of
peritoneum to the left of the rectum is split; the body of the fifth
lumbar vertebra, just under the bifurcation of the vessels is exposed;
the bone is trephined and one-half (the female portion) of a silver
cannula, exactly the size of the trephine, is inserted and held in
position. The child is then turned on his face and a laminectomy
performed; the subarachnoid space is opened, the strands of the cauda
separated, and the posterior half (male portion) of the cannula is
invaginated, so that it locks into the portion inserted anteriorly. Both
wounds are then closed. The fluid for a time finds its way into the
peritoneal cavity, but ultimately into the retro-peritoneal space whence
it is taken up by the receptaculum chyli, as experimental observations
have shown.’

Cushing has carried out this operation in 12 cases with a considerable
degree of success.

Recently, another method of treatment has been carried out by
Cotterill.[16] A large semilunar flap is made from the occipital region,
exposing the bone. Trephine circles are made on either side of the
median ridge, and the intermediate part of the bone, together with the
posterior part of the foramen magnum, is removed. The dura mater is
opened and the occipital sinus ligatured. The lateral lobes of the
cerebellum are then held apart, and the thickened arachnoid over the
posterior part of these lobes and over the roof of the fourth ventricle
exposed. This roof is opened. The wound is then closed.

By this method drainage from the ventricle is said to be reestablished.
Though without personal experience of this extensive procedure, one
cannot avoid expressing considerable doubt as to its advisability.

My own experience would lead me to the following conclusions:--

1. Whilst recognizing that internal hydrocephalus usually demands
surgical interference, it is only in some few cases that material
benefit results. Some recent successful cases point to the possibility
of better results in the future.

2. The operation which promises the best results, combined with
the least risk to the patient’s life, is that described as
ventriculo-subdural drainage.

[4] _Der Hirnbruch und seine Behandlung._ Moscow, 1896.

[5] _De la céphalhydrocèle traumatique_ (_Travaux de Neur. Chir._, iii.
1898).

[6] _Archives Italiennes de Biologie_, vol. xxxviii, p. 444.

[7] _Der Hirnbruch und seine Behandlung._ Moscow, 1896.

[8] _Beitr. zur klin. Chir._, vol. iii, p. 228.

[9] _St. Bart. Hosp. Reports._ Lawrence Ward. May 5, 1896.

[10] _Beitr. zur klin. Chir._, vol. vii, p. 228.

[11] _American Practice of Surgery._ Bryant and Buck.

[12] _Tumours, Innocent and Malignant._ Bland Sutton.

[13] _Brain_, 1902, p. 140.

[14] In estimating the size of the head, the following tables--after
Bonnifay--will be useful:--

           _Age._               _Circumference of head_ (average).

  Birth to fifteenth day          343 millimetres (approximate).
  Fifteenth day to 2 months       368      „             „
  At 3 months                     388      „             „
  Six months to 1 year            429      „             „
  One year to 2 years             459      „             „

_Normal rapidity of growth of the head_

  During the first 3 months        44 millimetres (approximate).
  During 3 to 6 months             41      „             „
  From 6 months to 1 year          30      „             „
  During second year               14      „             „

It should be noted that enlargement of the head can only take place
during the years previous to synostosis of the skull bones. Leonard
Guthrie (Harveian Lecture, March 17, 1910) writes, ‘I cannot find from
any recorded cases of hydrocephalus acquired in later childhood and
adult life that an increase in the size of the head has been any aid to
diagnosis, and I believe it is true that internal hydrocephalus acquired
after the sutures are set is hardly distinguishable from a
non-localizable intracranial new growth giving rise to headache,
vomiting, and optic neuritis.’

[15] The treatment for acquired hydrocephalus dependent on tumour
formation is discussed elsewhere. This section deals with the congenital
variety and with those cases of acquired hydrocephalus not due to
obstruction by tumours.

[16] _Review of Neurology and Psychiatry_, vol. ix, No. 1, p. 1.




CHAPTER IV

FRACTURES OF THE SKULL


=General considerations.= Fractures of the skull do not form more than
one-twentieth part of the fractures admitted annually into the
hospitals, but, in spite of this relative infrequency of occurrence, the
difficulties attendant on diagnosis, the numerous associated
complications, and the all-important question of treatment, invest this
subject with a special interest.

The whole question of skull fractures is beset with difficulties, many
of which, it is hoped, will be swept away in this and subsequent
chapters.

Brief allusion must first be made to some important points in connexion
with the anatomical structure of the skull, such as bear relation to
fractures and aid in the appreciation of the extent and mechanism of the
fracture.

The =vault= varies in density to a remarkable degree, not only in its
several parts, but also in different individuals. Cases have now and
again been recorded in which a very trivial blow, totally insufficient
to produce any definite osseous lesion in the normal individual, has
resulted in the production of a vault or basic fracture. Each case,
therefore, must be judged on its own merits.

The vault derives its strength from its shape and structure. The two
tables are of equal strength, and, for the most part, separated from one
another by a variable amount of diploic tissue. This diploe is most
abundant in the frontal, parietal, and upper occipital regions. These
parts are proportionately strong. Two regions are practically devoid of
this inter-tabular buffer--the squamo-temporal and cerebellar (see Figs.
29 and 30). A recognition of this comparative weakness is of great
practical importance in view of the fact that both these regions are
liable to special lesions--injury to the middle meningeal artery in the
first case, and, in the second, cerebello-medullary lesions. Nature’s
‘mistake’ in providing coverings unsuited to requirements has been
compensated for in part by additional protection--the temporal and
nuchal muscles.

[Illustration: FIG. 28. DIAGRAM ILLUSTRATING THE LINES ALONG WHICH
FORCES RECEIVED ON THE VAULT ARE TRANSMITTED TO THE BASE. (For further
description, see text.)]

Further, not only does the skull vary in density in its several parts,
but it is also ribbed and strengthened by various bony bars and
buttresses that pass up from base to vault (see Fig. 28). These
‘ribbings’ are seen to extend upwards from the crista galli, from the
external angular frontal process, from the auditory region, and from the
occipital protuberance. Presumably, these ‘ribbings’ were so constituted
for a definite purpose; in any case, it is clear that they play an
important part in the reception and conduction of forces to the base of
the skull. It is apparent, moreover, that the parts intervening between
these ‘ribbings’ are liable to injury in direct proportion to their
general position and strength. The deep groovings of the bone for the
reception of the middle meningeal artery afford an additional source of
weakness to the bone in the squamo-temporal region. (See Fig. 50).

[Illustration: FIG. 29 A. THE BASE OF THE SKULL.]

[Illustration: FIG. 29 B. THE BASE OF THE SKULL AS SEEN ON
TRANSILLUMINATION.]

Further reference will be made to the relative strengths of the various
regions of the skull. Sufficient has been said to show that nature has
provided the skull with various paths by means of which forces applied
to the vault can be conducted and distributed to the base.

Before, however, proceeding to discuss the effects produced on the base
of the skull, it is necessary to add that nature provides other methods
by means of which the intensity of a blow, delivered over the vertex of
the skull, is diminished. The forces are broken up and distributed in
the following manner:--

1. Though the force tends to travel in the direction of the applied
force, yet the convexity of the skull allows of the dissemination of
that force over a large superficial area.

2. The intervention of cartilage or fibrous tissue between two or more
of the component bones of the vault tends to diminish the intensity of
the force, to break it up and to alter its direction.

3. The bony ridges, along which the forces tend to travel, themselves
terminate blindly (see Fig. 28). Thus,

(_a_) Forces passing from the frontal region converge, more or less, to
the crista galli.

(_b_) Forces from the external angular frontal process pass along the
wings of the sphenoid bone to the anterior clinoid process.

(_c_) Forces from the auditory region are projected along the summit of
the petrous bone towards the apex of that process and to the posterior
clinoid process.

(_d_) Forces applied to the occipital region travel inwards along the
internal occipital crest to the strengthened margins of the foramen
magnum, or are projected outwards along the lateral sinus ridges. In the
former case, the force either passes forwards towards the dorsum ephipii
and so again reaches the posterior clinoid process, or is directed more
laterally towards the jugular process of the occipital bone, there
meeting the fibrous tissue intervening between that process and the
corresponding part of the temporal bone.

4. All forces, whether transmitted along the internal occipital crest,
the temporal bone, the sphenoidal wings, or the crista galli of the
ethmoid, are further transmitted to the dura mater attached to those
prominences and ridges. The dura mater undoubtedly plays an important
part in the reception and transmission of the forces.

5. The forces all show a tendency to converge towards the pituitary
region, the great ‘water-cushion’ of the brain--a region bounded by the
clinoid processes. That these processes receive a considerable part of
the forces transmitted is confirmed by the fact that they are frequently
torn away from their basic attachments. This is especially the case with
respect to the attenuated base of the anterior clinoid process.

It is obvious, therefore, that forces tend to be transmitted from the
vault to the base, and yet the base is, in many respects, the weakest
part of the skull. It is perforated by numerous foramina, it is hollowed
out in places for the formation of air sinuses and for the reception of
the integral portions of the auditory apparatus. Furthermore, it
presents a more or less plane surface, one differing in all respects
from the marked convexity of the vault. Those forces, therefore, which
are received by the base of the skull are not subjected to that
diffusion which forms so conspicuous a feature in the case of the vault.

All these points tend to show that the base of the skull is more or less
unsuited for the reception of severe blows, direct or transmitted,
whilst, on the other hand, nature has taken into consideration and
provided fairly adequately against the dangers incident to vault
injuries.

It is not proposed at this stage to discuss further the relative
strength of vault and base. Points, other than those already enumerated,
will be brought forward in subsequent sections.


FRACTURES OF THE BASE OF THE SKULL

Fractures of the base of the skull are produced in two ways:--

1. By violence applied _directly_ to the base--perforating wounds of the
orbit, bullet-wounds through the mouth and base of skull, the driving
inwards of the bones of the face, the driving upwards of the condyle of
the jaw (the ‘knock-out’ blow of the pugilist), and, as the result of
heavy falls on to the feet or buttocks, the upward driving of the
condyles of the occipital bone.

2. By violence applied _indirectly_--blows applied directly to the vault
and transmitted to the base. This variety will be considered first as it
receives the greatest prominence in surgical textbooks. Various
explanatory theories have been advanced, of which the following are the
more important:--


(_a_) =Aran’s theory of irradiation.= This theory states that ‘fractures
of the base result as extensions from fractures of the vault, the
fracture following the shortest anatomical route to the base’. Although
this theory must be accepted as offering a satisfactory explanation for
the occurrence of a certain proportion of basic fractures, such, for
instance, as result from a blow applied directly to the vertex, it
certainly cannot be accepted as accounting for the great majority of
basic fractures. The theory was advanced on the hypothesis that basic
and vault fractures were necessarily co-existent. That combined lesions
of this nature are frequently in evidence is not to be doubted for one
instant. It is, however, ‘putting the cart before the horse’ to say that
the vault fracture is always the primary lesion. Such is by no means the
case.


(_b_) =The bursting and compression theories.= The skull is here
regarded as an highly elastic sphere, compression of which leads to
diminution in the diameter along the axis of greatest pressure, bulging
occurring in other diameters. The bulging exceeding the limits of
elasticity a fracture occurs, the line of fracture varying according to
the different features present. Thus, when the lines of fracture run
parallel to the direction of the compressing force the bone bursts open
along the convexity (bursting fractures), and when the lines of fracture
run at right angles to the direction of the compressing force a fracture
by compression is said to result (compression fractures).

These theories are based on experiments carried out on the cadaver, the
skull being enclosed in a tight-fitting box and subjected to pressure
sufficing to bring about a fracture. Undoubtedly, the head may be
compressed between two forces, as, for instance, when a person is
knocked down in the street, the vehicle passing over the head, or, as in
a case recently under my care, where a boy, hanging by his feet from the
side of a barge, was crushed between the barge and the wharf as the
vessel swung inwards with the tide. Cases of bilateral compression are,
however, of infrequent occurrence, the great majority of basic fractures
resulting from blows applied directly at the region of the level of the
base of the skull (see p. 76), or from the forward propulsion of the
body, the head coming into violent contact with a resisting object, as,
for instance, when a person is thrown out from a motor-car, the head
striking against a tree, brick wall, &c. In the first case, there can be
no question of bilateral compression, and in the second the compression
is exerted between the vertex and the occipital condyloid region.

Moreover, the fundamental points on which the bursting and compression
theories are grounded are based on erroneous principles. The skull
cannot in any sense be regarded as a sphere, nor does it possess the
requisite elasticity to bulge and allow of compression in the manner
that the theory demands. The skull, in reality, forms rather less than
two-thirds of a sphere, the base passing inwards from the lower limits
of this partial sphere in a more or less horizontal plane. This can be
readily verified by placing the skull on a table so that its base
corresponds to the surface of the table. The elastic properties of the
skull have also been greatly exaggerated, and far too little attention
has been paid to the peculiar anatomical formation of the base.


(_c_) =The contre-coup theories.= Fractures of the base occasionally
occur in which evidence is conclusive that the blow was received on the
vault, the vault itself remaining uninjured. Such cases have given
origin to this theory, one stating that ‘from the point struck a wave is
transmitted through the semi-fluid brain, producing a fracture at some
more distant point’. Helferich, for instance, maintains that isolated
fractures of the orbital roof, and more rarely of other parts of the
base, are produced by the influence of hydrostatic pressure. There can
be no question that waves are transmitted through the brain and
cerebro-spinal fluid, but that such waves should be capable of producing
a basic fracture is, in my opinion, beyond the bounds of possibility.
The theory is opposed to all my experience of basic fractures, and the
cases brought forward in support are capable of a much more probable
explanation. The base is undoubtedly the weakest part of the skull, and
a blow on the vault may fail to produce a local lesion and yet, when the
force is transmitted to the weaker base, may there bring about a more
definite result. For instance, it is by no means uncommon to find that a
blow on the frontal region fails to fracture the vertical plate of that
bone and yet suffices to produce a fracture, often comminuted, of the
orbital plate of the frontal bone or of the cribriform plate of the
ethmoid, two fragile plates, either of which may shatter like a plate of
glass from the effect of forces transmitted across them. In further
support of this theory, the following case, recently under my care, may
be cited. The patient received a heavy blow over the left occipital
region. A fracture passed inwards across the left cerebellar fossa
towards the posterior border of the foramen magnum, and a second
fracture, entirely distinct from the first, passed across the right
orbital plate of the frontal bone. In this case, the force conducted
across the base, from behind forwards, failed to fracture the strong
basi-occiput, but succeeded in producing a more definite lesion on
reaching the fragile orbital plate.

Some of the celebrated surgeons of the last century insisted that the
course pursued by basic fractures was to be explained on anatomical
grounds, but their views have been neglected and theories based on
experimental evidence have been accepted in their place. All
experiments, such as those previously mentioned, are useless, and
definite conclusions can only be gained by carrying out in every case
the following method of investigation: (1) by obtaining in the first
case an accurate history as to the manner in which the injury was
received; (2) by noting all visible and palpable signs of external
injury; (3) by careful observation of all the clinical symptoms during
the progress of the case; (4) by comparison of such with the lesions
found in case of death.

Over 300 cases have been investigated by me after these principles. In
about 30 per cent. of the cases sufficient evidence was obtained to show
that the basic fracture resulted and extended from a primary fracture of
the vault. These cases were to be explained by Aran’s theory of
irradiation. This theory, however, errs in stating further that the
fracture follows the shortest anatomical route to the base. This is not
correct, for the line of fracture corresponds to the direction of the
applied force and is influenced to a very large extent by the resistance
offered, the weaker areas being picked out and the strong buttresses
avoided. It is only in the most severe cases that the fracture travels
to and traverses across the base in such a direction as to show that,
for the time being, all laws are in abeyance.

In about 5 per cent. of cases the fracture resulted from bilateral
compression, from falls on to the buttocks, &c., and from blows applied
to the angle of the jaw. These cases afforded examples of the bursting
and compression theories.

On the other hand, in over 60 per cent. of cases, the injury was
received over one of the following situations: (1) in front, over the
frontal eminence or supra-orbital ridges; (2) in the antero-lateral
region, over the external angular frontal process; (3) in the lateral
region, over the lower temporal, auricular, and mastoid regions; (4) in
the posterior region, over the superior curved line of the occipital
bone or over the external occipital protuberance.

In all these cases, therefore, the blow was inflicted at or near the
level of the base of the skull, the resultant fracture being a fracture
by direct violence, the fracture traversing the base and splitting it
much in the same way as a chisel splits a board of wood. The ‘grain’ of
the wood may be regarded as representing the weaker basic lines, and any
‘knot’ the resistance offered by the strong basic buttresses, the forces
being momentarily turned aside, but soon again passing onwards, parallel
to the original direction, but not necessarily in the same straight
line.

[Illustration: FIG. 30. PLAN OF THE BASE OF THE SKULL. _a_, _a_, The
transverse pre-condyloid line; _a′_, _a′_, The line pursued, in whole or
in part, by the ‘typical’ basic fracture.]

Any blow delivered at or near the basic level tends _primarily to
involve the weaker area, the base, passing secondarily upwards on to the
vault_. One may go even so far as to say that in most combined vault and
basic fractures, the vault fracture is a secondary development, the
basic fracture being the primary lesion.

There is, however, still another important anatomical feature bearing
on the mechanism of basic fractures, one that must necessarily come into
force in the greater number of such fractures. The base of the skull may
be said to consist of two parts, one lying anterior to the condyles of
the occipital bone, the other posterior to and including the condyles
with their vertebral attachment. These two segments are united to one
another by a weak chain--represented by a line drawn from one external
auditory meatus to the other, with, as a connecting link, the sphenoidal
sinus in the middle line.

When the base of the skull is viewed from below, it will be seen that
the weak line includes both Glaserian fissures, both petro-sphenoidal
sutures, both foramina lacera media, with the sphenoidal sinus again as
a connecting link. The two parts of the skull are, to all intents and
purposes, merely cemented together by the union of the basi-sphenoid and
basi-occiput. Consequently, if a blow be received on the antero-lateral
region of the head, the anterior segment tends to be split off from the
more fixed posterior part, the fracture following the weak line
previously indicated. This weak line occupies so important a position in
the mechanism of basic fractures that careful observation will show that
the greater number of middle fossa fractures follow that line, wholly or
in part. Such a fracture of the middle fossa may be termed ‘the typical
fracture of the base of the skull’ (see Figs. 30, 34 and 39).


=Summary of theories.= Aran’s theory of irradiation, with certain
modifications, accounts satisfactorily for about 30 per cent. of basic
fractures.

The contre-coup theory may be rejected entirely.

The bursting and compression theories are unsatisfactory, accounting for
not more than about 5 per cent. of fractures.

The majority of cases result from direct violence applied at or near the
basic level, the fracture passing across the base in the general
direction of the applied force, but not necessarily in the same straight
line.

Up to this point certain facts and theories have been discussed, such as
bear on the general mechanism of basic fractures. It now remains to
consider other factors that exercise influence on the general direction
of the fracture.


=The influence of sutures on the line of the fracture.= Complete
maceration of the skull is always essential in endeavouring to estimate
in what way the various sutures of the skull influence the extent and
direction of a fracture. Sutural separation is generally regarded as of
infrequent occurrence. An examination of a large number of macerated
skulls has shown, however, that sutural separation is in reality of
common occurrence. Certain sutures show a special liability to such
changes, especially the masto-occipital, the petro-occipital, and the
petro-sphenoidal. Separation of the sutures is more common in the young
adult; in the infant and in the old such conditions are seldom observed.

Allusion has already been made to the fact that forces transmitted from
the vault to the base, or vice versa, undergo a marked diminution in
intensity when the sutures of the skull are encountered, the ‘fracture’
showing a marked disposition to follow the line of the suture. When the
force is excessive, all rules are temporarily in abeyance, but, under
ordinary circumstances, the separation along the line of a suture
corresponds fairly accurately with the dentations and serrations of the
suture involved. Sutural separation without actual fracture is a
possible occurrence, but is decidedly rare. Such isolated fractures are
confined, more or less, to the sagittal suture in the vault, and the
masto- and petro-occipital sutures in the base.


=The influence of air-sinuses, &c., on the line of the fracture.= The
_sphenoidal sinuses_, two in number, are usually separated from one
another by a thin septum. This septum is, however, often deficient, and
a single cavity exists. The sinuses make their appearance about the
seventh or eighth year; they vary greatly in size but, when fully
developed, occupy the greater part of the so-called body of the
sphenoid, extending backwards almost as far as the junction of the
basi-sphenoid and basi-occiput, and spreading outwards into the wings of
the sphenoid and over the roof of the orbit.

The sinus is bounded on all sides by a thin lamella of bone; its roof
forms part of the middle fossa of the skull, the sides are separated by
a thin bony wall from the cavernous venous sinus, and the floor aids in
the formation of the roof of the naso-pharynx. There exists, therefore,
in the very centre of the base of the skull--in the region of the
so-called buttress of connexion between the posterior and anterior
segments of the skull--an exceedingly weak area, one which must be
implicated in the great majority of basic fractures. The ‘weak line’ of
the base of the skull--previously referred to--is now still more
accentuated.

The sphenoidal sinus is involved in at least 40-50 per cent. of basic
fractures, comminution of the sinus wall being often so excessive that a
probe can be passed with the greatest ease from the middle fossa into
the naso-pharynx. Blood is thus allowed to escape readily into the
naso-pharynx, and a source is opened up for the possible development of
meningeal infection.

Reference to the various illustrations of fractures of the base will
supply further evidence as to the special liability of the sinus region
to injury. It will be seen that nearly all fractures that pass one
middle fossa to the other, or from one middle fossa to the opposite
anterior fossa, traverse this region.

The _frontal sinuses_, also two in number, are separated from one
another by a thin osseous septum. Up to the age of puberty these sinuses
are either absent or represented by a small cell. Subsequently, they
develop rapidly, often extending into the orbital roof. The upper and
inner boundary--usually very fragile--assists in the formation of the
anterior fossa of the skull. The outer boundary--the perpendicular plate
of the frontal bone--is much more dense, and, consequently, a fracture
of the outer wall is almost necessarily associated with a fracture
involving the inner or orbital boundary, that is to say with a fracture
of the anterior fossa.


_The ethmoid cells._ The ethmoid bone consists of a collection of cells
which communicate with the nasal cavity (middle and superior meati), and
which are merely separated from the anterior fossa of the skull by the
thin cribriform plate. This plate of bone is of so fragile a nature that
splintering occurs in the great majority of anterior fossa fractures.
The special dangers that arise from the possibility of meningeal
infection are obvious.


_The auditory region._ That part of the petrous bone which encloses the
auditory apparatus, and which transmits the seventh and eighth pair of
nerves, is proportionately weakened and correspondingly liable to
fracture. The special details of these fractures are dealt with on p.
102.

[Illustration: FIG. 31. TO ILLUSTRATE THE RELATION OF BASIC FRACTURES TO
CRANIAL NERVES.]


=The influence of basic foramina.= It has often been stated that a basic
fracture is arrested on meeting one of the larger foramina of the skull.
With this view I am not in agreement, for not only are the larger
foramina frequently involved, such as the foramen lacerum posterium and
medium, but the largest foramen of all, the foramen magnum, is often
implicated. It will be granted that certain foramina are but rarely
involved, but this is due to the fact that they are aside of the chosen
and definite paths of basic fracture. Thus, the foramen ovale and the
foramen spinosum are only exceptionally involved because they lie
immediately anterior to the petro-sphenoidal suture, whilst the anterior
condyloid foramen--transmitting the hypoglossal nerve--is rarely
implicated because it lies internal to the usual posterior fossa
fracture. On the other hand, the foramen lacerum medium is involved in
nearly every fracture that passes from one middle fossa to the other.


=The probable line of basic fracture in any given case.= When the
various weaker lines and areas are taken into consideration, and when
the direction and site of the applied force are known, one is generally
enabled to foretell with considerable accuracy the probable transbasic
course of the fracture. After investigating over 300 cases, I was
enabled to frame the following rules with respect to the probable line
of transbasic fracture.

  _Direction, &c., of       _Probable resultant basic fracture._
  the applied force._

  1. Force applied to The fracture passes backwards from the
  the median frontal  perpendicular plate of the frontal bone to the
  region.             cribriform plate of the ethmoid, thence between
                      the optic foramina to the body of the sphenoid,
                      the thin sinus roof being usually comminuted. From
                      there the fracture diverges to the opposite side,
                      and tearing off the posterior clinoid process,
                      passes along the petro-occipital suture to the
                      jugular foramen, being then continued on the other
                      side of that foramen along the masto-occipital
                      suture, and so again to the vault.

  [Illustration: FIG. 32. DIAGRAM OF LINES PURSUED BY BASIC FRACTURES.
  Force applied to the median frontal region.]

  2. Force applied to The fracture passes across the anterior fossa
  the lateral frontal towards the sphenoidal fissure, tearing away the
  region, in the      anterior clinoid process, and again comminutes the
  situation of the    roof of the sphenoidal sinus. Progressing onwards,
  external angular    with or without fracturing the posterior clinoid
  frontal process.    process, the fracture passes either along the
                      anterior part of the petrous bone at its junction
                      with the greater wing of the sphenoid towards the
                      opposite middle and external ears, or along the
                      petro-occipital suture to the jugular foramen, and
                      continued along the masto-occipital suture as in
                      the previous case.

  [Illustration: FIG. 33. DIAGRAM OF LINES PURSUED BY BASIC FRACTURES.
  Force applied to the lateral frontal region in the situation of the
  external angular frontal process.]

  3. Force applied to The fracture passes across the roof of the bony
  the region of the   auditory meatus towards the junction of the
  external ear.       anterior and inner walls of the middle ear,  the
                      membrane undergoing a variable amount of
                      destruction and displacement. The fracture is then
                      continued across the tegmen tympani, and after
                      following the petro-sphenoidal suture reaches the
                      foramen lacerum medium, being again continued on
                      the opposite side of that foramen to  the
                      sphenoidal body. Thence it pursues one of two
                      courses. Most commonly the fracture passes
                      backwards obliquely to the opposite middle and
                      external ears, following a course similar to that
                      already indicated.

                      In such cases the fracture may extend on each side
                      up on to the vault in such a manner that the two
                      segments are merely united by the soft parts;
                      whether the fracture be so complete or not, a more
                      minute examination of the line of separation will
                      evidence many interesting points. An inspection of
                      the anterior aspect of the posterior fragment
                      shows that the fracture passes just in front of
                      the geniculate ganglion of the facial nerve, the
                      ganglion being laid bare, whilst its petrosal
                      branches are usually torn. The fracture also
                      passes anterior to the Eustachian tube and the
                      horizontal part of the internal carotid artery. On
                      examining this posterior fragment the following
                      structures will be seen, passing from without
                      inwards: the posterior half of the external
                      auditory meatus, the mastoid antrum, the lacerated
                      membrane and the ossicles of the middle ear, the
                      geniculate ganglion of the facial nerve, the
                      Eustachian tube, the horizontal part of the
                      internal carotid artery, the Gasserian ganglion,
                      and the posterior half of the sphenoidal sinus in
                      the middle line (see also Fig. 39).

                      After reaching the sphenoidal body, the
                      alternative course for the fracture to pursue is
                      to pass towards the opposite sphenoidal fissure
                      and, tearing off the anterior clinoid process, to
                      be directed across the anterior fossa, parallel to
                      the original direction but not in the same
                      straight line.

  [Illustration: FIG. 34. DIAGRAM OF LINES PURSUED BY BASIC FRACTURES.
  Force applied to the region of the external ear. _a_ ... _a_, The
  ‘typical’ basic fracture (see also Fig. 30).]

  4. Force applied to The fracture follows the occipito-mastoid suture
  the mastoid region. to the jugular foramen, and is again continued on
                      the opposite side of that foramen along the
                      petro-occipital suture towards the apex of the
                      petrous bone. It then passes across the sphenoidal
                      body to the sphenoidal fissure of the opposite
                      side, and so across the anterior fossa. It is
                      especially common in this particular variety of
                      fracture to find fissures diverging from the
                      region of the sphenoidal sinus forwards towards
                      the cribriform plate of the ethmoid, these
                      fissures usually passing between the optic
                      foramina.

                      This fracture is also peculiar in so much that,
                      when the degree of separation along the
                      occipito-mastoid suture is excessive, there is
                      special liability to a tearing of the lateral
                      sinus wall as the sinus begins to turn downwards
                      and inwards.

  [Illustration: FIG. 35. DIAGRAM OF LINES PURSUED BY BASIC FRACTURES.
  Force applied to the mastoid region.]

  5. Force applied to The fracture passes across the thin cerebellar
  the lateral         fossa and strikes the foramen magnum immediately
  occipital region.   behind the condyle. Starting again from a similar
                      point on the opposite side of the foramen, the
                      fracture passes outwards to the jugular foramen.
                      Again, two courses are now available, the fracture
                      either cutting outwards across the body of the
                      petrous, ‘external’ to the internal auditory
                      meatus and cutting across the facial nerve in the
                      region of the geniculate ganglion, and finally
                      terminating in the roof of the middle ear, or else
                      passing along the petro-occipital suture and so to
                      the foramen lacerum medium, the sphenoidal
                      fissure, and the anterior fossa as in the previous
                      case.

  [Illustration: FIG. 36. DIAGRAM OF LINES PURSUED BY BASIC FRACTURES.
  Force applied to the lateral occipital region.]

  6. Force applied to The resultant fracture varies according to the
  the posterior       direction of the applied force. A force which is
  occipital           applied to the posterior occipital region at right
  region.             angles to the transverse axis of the skull results
                      in a fracture which, on reaching the posterior
                      margin of the foramen magnum, is continued again
                      on the opposite side of the foramen along the
                      dorsum ephipii. When the force is more oblique in
                      direction (as is usually the case) the fracture
                      traverses the thin cerebellar fossa to the outer
                      margin of the jugular foramen, and then follows
                      one of the two courses indicated in the previous
                      case.

                      More commonly the fracture cuts across the petrous
                      bone.

  [Illustration: FIG. 37. DIAGRAM OF LINES PURSUED BY BASIC FRACTURES.
  Force applied to the posterior occipital region, the fracture
  following the course _a. a._ or _b. b._, according to the direction of
  the applied force.]


=Summary.= Basic fractures tend to follow certain definite paths, this
transbasic course varying according to the direction of the force
applied and the site of application of the same. Whether the fracture
completely traverses the base depends on the character of the force and
the resistance offered, for bases, as well as vaults, vary greatly in
strength. To every rule there must be exceptions, and cases are at hand
in which the fracture appears to have obeyed no law, or in which the
force applied was of so forcible a nature that the fracture traversed
the base, regardless of all the ordinary rules.

The principles enumerated above were formulated by me some four years
ago, and, in spite of certain adverse criticisms, I am more than ever
convinced that the rules are correct, and that time and research are
alone required to add to the strength of my assertions.


SYMPTOMS RESULTING FROM FRACTURE OF THE BASE OF THE SKULL

The symptoms resulting from a fracture of the base of the skull vary
according to the particular fossa fractured. From a general point of
view, the following symptoms require consideration:--

Hæmorrhages.

Escape of cerebro-spinal fluid.

Escape of brain-matter.

Escape of air from the air-sinuses into the surrounding tissues.

Involvement of certain cranial nerves.


Symptoms pointing to fracture of the Anterior Fossa.


=Hæmorrhages=: (_a_) _Subconjunctival hæmorrhage_ usually makes its
appearance at the outer canthus of the eye, progressing inwards towards
the corneo-scleral margin, and, in the most severe cases, completely
surrounding the cornea, bulging the conjunctiva forwards in such a
manner as to constrict the field of vision. The extravasated blood is
usually bright red in colour, makes its appearance within a few hours of
the accident, and reaches its maximum within thirty-six to forty-eight
hours.

In some cases a condition of subconjunctival œdema (chemosis) is
observed. This also usually originates at the outer canthus.

Taken by themselves, neither hæmorrhage nor œdema are of any great
diagnostic value. Both conditions, however, aid materially in confirming
the diagnosis.

The blood is almost invariably completely absorbed, and no ill effects
remain.


(_b_) _Palpebral and peri-palpebral hæmorrhage_ is seen in most cases of
fracture of the anterior fossa. This form of hæmorrhage differs from the
one mentioned above in that it usually commences at the inner canthus of
the eye, thence progressing in the outward direction. The extravasated
blood may be wholly anterior to the suspensory ligaments of the lid, in
which case it may be surmised that the fracture only involves the
perpendicular plate of the frontal bone. More commonly, however, the
cribriform plate of the ethmoid shares in the lesion, in which case
palpebral, peri-palpebral, and subconjunctival hæmorrhage are all
present.


(_c_) _Orbital hæmorrhages_ may be so extensive that marked forward
protrusion of the globe exists. The time at which proptosis makes its
appearance, and the degree to which it progresses, vary according to the
nature of the lesion. Thus:--

  Proptosis severe, appearing    implies   a fracture associated with
  almost at once,                          injury to the cavernous sinus
                                           or internal carotid artery.

  Proptosis moderate, and           „      a fracture involving the
  appearing after a few hours,             walls of the orbit, the blood
                                           being derived from lacerated
                                           ethmoidal and other small
                                           vessels.

  Proptosis appearing days or       „      a fracture involving the
  weeks after the accident,                region of the sphenoidal body
  usually progressive,                     and complicated by the
                                           formation of a fistulous
                                           communication between the
                                           cavernous sinus and the
                                           carotid artery (see Traumatic
                                           orbital aneurysm).


(_d_) _Retinal hæmorrhages._ Fleming, in 1902, reported 12 cases of
fracture of the skull, all except one being fractures of the base, in
which retinal hæmorrhages were present. All cases were associated with
hæmorrhage into the subarachnoid space, and when this hæmorrhage was of
a unilateral nature the retinal changes were likewise one-sided. It was
also found that in 4 cases of cerebral hæmorrhage without osseous
lesion retinal hæmorrhages were present in three, these three being all
associated with considerable effusion into the subarachnoid space.

These observations are not only of value in the general diagnosis of
intracranial lesions, but are also of considerable importance in the
differential diagnosis between extra- and intradural hæmorrhages.


(_e_) _Hæmorrhage from the nose and mouth_ is almost invariably present
in fractures of the anterior fossa, with the inference that the fracture
involves the cribriform plate. The blood--derived mainly from lacerated
ethmoidal vessels--escapes from the anterior nares or, passing back into
the naso-pharynx, escapes by the mouth or is swallowed, to be vomited up
later.


=Escape of cerebro-spinal fluid.= Blandin, of the Hôtel-Dieu, drew
attention to this condition in the year 1840. The fracture involves the
cribriform plate of the ethmoid, and is associated with laceration of
the overlying dura mater and arachnoid, and of the prolongations of
those membranes along the olfactory nerves.

The escape of cerebro-spinal fluid from the nose may be regarded as
diagnostic of a fracture of the anterior fossa, in spite of the fact
that Goucard, Malgaigne, and others describe cases in which, as the
result of a severe fracture of the petrous bone (middle fossa) without
laceration of the membrana tympani, the fluid escaped along the
Eustachian tube to be expelled by mouth and nose.

  At this stage, it will be necessary to allude more fully to the
  general question of cerebro-spinal discharge from the nose, mouth, and
  ear. The symptom is an important one, though undoubtedly of far less
  frequent occurrence than stated in text-books. This was proved by
  Crandon and Wilson, who reported 27 cases in which there was a
  cerebro-spinal discharge out of a total number of 530 cases examined.
  Phelps mentions 13 in a series of 286 cases of fractured base. My
  experience coincides with these statements.

  The escape of a slightly blood-stained fluid from the ear and nose
  does not necessarily imply that the fluid is cerebro-spinal in nature,
  for it has been proved on numerous occasions that fluid may escape in
  considerable quantities without the existence of a basic fracture. In
  such cases the fluid is derived either from the membranous labyrinth
  (the liquor cotunnii) or from the mucous membrane lining the ear and
  nose, the result of great vaso-motor dilatation of aural and nasal
  vessels.

  If the fluid be cerebro-spinal in nature, the natural inference is
  that the subarachnoid space is opened up to the exterior, either
  directly or indirectly along the course of a cranial nerve. A chemical
  analysis of the fluid will determine the nature thereof, provided that
  the fluid be collected EARLY.

  Thus, cerebro-spinal fluid is  whilst  fluid derived from other
    rich in chlorides, contains          sources contains chlorides, a
    little or no albumen, but            fair amount of albumen, and no
    shows a trace of a reducing          sugar.
    substance, allied to
    pyro-catechin,

  Certain factors, however, must be taken into consideration which
  diminish the value of these chemical tests, for, though the fluid be
  cerebro-spinal in nature, the admixture of blood at once interferes
  with the delicacy of the test. Furthermore, even in the event of a
  profuse discharge of cerebro-spinal fluid, the first part collected
  alone contains sugar, the discharge soon becoming nothing more or less
  than a serous exudation.

  The fluid is almost certainly cerebro-spinal if the discharge begins
  within twenty-four hours of the accident, if it be practically
  colourless, fairly profuse, and continuing for two or three days,
  perhaps longer.

  Though the discharge usually originates early, cases are recorded in
  which the flow commenced some weeks after the accident. The discharge
  may continue for hours or for weeks. Sir W. Savory recorded a case in
  which fluid escaped for one month from both ears. The quantity also
  varies greatly, usually a few ounces, but sometimes many pints. Sir W.
  MacCormac recorded a case in which 10 pints escaped within five hours.
  A profuse discharge is due to the fact that, as the original
  cerebro-spinal fluid drains away, its place in the subarachnoid space
  is taken by a serous exudation from the cerebral venous system. This
  exudation occurs as soon as the subarachnoid pressure is sufficiently
  reduced, the serous exudation progressing till the venous and
  cerebro-spinal pressures are again equal.

  As regards the _prognosis_, it is interesting to note that the escape
  of cerebro-spinal fluid implies of necessity that the subarachnoid
  space is opened up to the exterior, with all attendant dangers of
  meningeal infection, yet that the prognosis is generally favourable.
  One might even go further and state that the prognosis in such cases
  is rather more favourable than under more ordinary circumstances.
  Thus, Battle records 36 cases with a mortality of 25 per cent., the
  general mortality of fractured base being about 44 per cent. My own
  experience tallies with these statistics. The more favourable result
  hinges no doubt on the fact that the prolonged outflow tends to wash
  away organisms existent in the aural and nasal passages.

  With regard to any special points in treatment, it is obvious that
  syringing of ear or nose is absolutely contra-indicated. The cavities
  should be _lightly_ plugged with gauze, the dressings to be renewed as
  soon as they are soaked. The patient must also be prevented from
  interfering with the dressings.

  With regard to the routine use of urotropin to guard against the
  advent of meningitis, see p. 116.


=Escape of brain-matter from the nose.= This diagnostic symptom is of
very rare occurrence. For its development the following factors are
requisite:--

Great comminution and destruction of the anterior fossa.

Severe local laceration of the brain (frontal lobes).

A copious discharge of blood and cerebro-spinal fluid.

A general increase in the intracranial pressure.

One case only of this nature has come under my own observation, that of
a man whose right nostril was blocked with brain substance. He died
shortly after admission into the hospital, and at the post-mortem
examination the above conditions were found.


=Escape of air from the air-sinuses into the surrounding regions.= When
the fracture involves the frontal, ethmoidal, and mastoid sinuses, any
sudden increase of the intrasinus air-pressure, such as is caused by
sneezing, blowing of the nose, &c., may force air into the surrounding
tissues. A distinction must be made between those cases in which the
pericranium overlying the seat of fracture is torn and those in which it
remains intact. In the former case, the escaping air may spread widely
into the neighbouring loose tissues, leading to a condition of ‘surgical
emphysema’. In the second case, the air remains confined to a smaller
area, giving rise to a soft, more or less rounded swelling. Gentle
palpation of this swelling imparts to the fingers that crackling
sensation peculiar to the condition. Firm pressure results in diminution
in the size of the tumour, the contained air being forced back into the
sinus cavity. Such localized collections of air are known as
‘pneumatoceles’.

As regards the special _treatment_ of these conditions, the patient
must, in the first case, be warned against straining of all sorts.
Pneumatoceles require no other treatment. The condition soon disappears
if the patient recovers. In widespread surgical emphysema, an incision
should be made over the injured sinus, thus allowing of the direct
escape of the air expelled from that sinus.


=The involvement of nerves.= The following nerves may be involved in
anterior fossa fractures:--


(_a_) _The olfactory nerve._ The great majority of anterior fossa
fractures traverse the cribriform plate, necessarily injuring the fine
branches of the olfactory bulb. The bulb itself may be lacerated, with
or without injury to the under surface of the frontal lobes. Sir
Prescott Hewitt considered that anosmia, or loss of smell, resulted most
frequently from blows applied to the back of the head, the frontal
region being injured by contre-coup. From my own experience it would
appear, however, that anosmia, whether uni- or bilateral, whether
transient or permanent, generally results from direct injuries of the
cribriform plate with associated lacerations of the olfactory nerves. It
is difficult to estimate the presence or degree of immediate loss of
smell on account of the general condition of the patient and because the
nostrils are usually more or less filled with blood coagulum. Experience
shows, however, that early loss of smell is the rule and total and
permanent anosmia the exception. Anosmia is usually associated with some
degree of loss of taste.


(_b_) _The optic nerve._ Many cases have been recorded in which visual
defects resulted from blows applied to the head. The blindness may be
partial or complete, immediate in onset or developing at some future
date. In the latter case, the loss of vision is due to retinal changes
or results from post-neuritic atrophy.

The occurrence of complete or partial blindness as the immediate result
of the injury is, at first sight, difficult to explain, for the vast
majority of anterior fossa fractures avoid the immediate vicinity of the
optic foramina, passing by preference between the two foramina or
diverging towards the sphenoidal fissures. Small fissured fractures not
infrequently radiate through the optic foramina, usually, however, of so
slight a nature as to be incapable of leading to any gross lesion of the
optic nerves. Hæmorrhage into the sheath of the nerve is probably
responsible for a certain proportion of cases, more especially those in
which there is a peripheral concentric loss of vision, the more central
fibres escaping. It is possible, also, that cases evidencing temporal
or nasal blindness may be due, as J. J. Evans[17] thinks, to a
contre-coup contusion of the nerve through it being forcibly driven
against the bony boundaries of the foramen. Taking into consideration,
however, the very frequent presence of a fracture through the anterior
clinoid process (see p. 82), and the usual displacement of that process,
it would appear probable that immediate and more or less complete loss
of vision results from the compression and crushing of the optic nerve
by reason of the pressure exercised by a displaced clinoid process.

The following statistics add confirmation to this view. Thus, Callen
collected 17 cases in which the optic nerve was compressed by osseous
fragments in the region of the optic foramen, whilst Holder observed
injury to the bones entering into the formation of the foramen in 53 out
of 86 cases of fracture involving this region.

The prognosis varies according to the cause of the blindness. When
resulting from concussion of the nerve trunk or from hæmorrhage into its
sheath, certain fibres may regain their function. In the majority of
cases, however, that have come under my own observation, blindness of
the affected eye was immediate and permanent.


(_c_) _The nerves passing through the sphenoidal fissure._ The
ophthalmic division of the fifth nerve is rarely injured to such a
degree as to cause anæsthesia of all the regions supplied. Blood
extravasation into the surrounding regions, or direct involvement of one
of the branches of the nerve, often results in areas of anæsthesia, and
some few cases have been recorded in which there was complete anæsthesia
of both cornea and conjunctiva, with subsequent ulceration and
sloughing. The nasal nerve may be implicated as the result of a fracture
involving the cribriform plate, whilst the supra-orbital and
supra-trochlear branches may be damaged by fractures of the vertical
plate of the frontal bone.

The third nerve is similarly liable to injury, in any part of its
orbital course. It is quite exceptional, however, for the whole trunk to
be affected, some of the branches being taken, others left. The fourth
nerve is also occasionally involved, generally in association with other
orbital nerves.

When anæsthesia or paralysis of muscles results from pressure exercised
on the nerves by extravasated blood, the ultimate prognosis is not
unfavourable. When due to direct implication, in the line of the
fracture, the prognosis is much more uncertain, partial or complete loss
of function resulting.


SYMPTOMS POINTING TO FRACTURE OF THE MIDDLE FOSSA


=External hæmorrhages.= (_a_) _Hæmorrhage into the temporal region._ The
extravasated blood may either be confined to the temporal
region--temporal hæmatoma--or diffused throughout the subaponeurotic
space. A temporal hæmatoma is always highly suggestive of a fracture
involving the temporal fossa, especially in the event of marked outward
bulging, with stretching and discoloration of the overlying tissues. In
many cases also the hæmatoma pulsates, in which case it can be presumed
that the fracture of the temporal fossa is associated with hæmorrhage
from a lacerated middle meningeal artery (see Fig. 38). In such cases
the application of pressure to the hæmatoma may lead to the development
of fits on the contra-lateral side, originating in the face or arm
regions and spreading to the higher cortical motor area.

[Illustration: A

B

FIG. 38. TO ILLUSTRATE THE PROBABLE SOURCE OF PROFUSE HÆMORRHAGE FROM
THE EAR. A, The fracture the roof of the external auditory meatus. B,
Comminution of the tegmen tympani, the fracture involving the groove for
the posterior branch of the middle meningeal artery.]


(_b_) _Hæmorrhage from the ear and mouth._ The great majority of middle
fossa fractures involve the external auditory meatus, passing inwards
across the roof and floor of the middle ear towards the body of the
sphenoid. Examination will show that the fracture passes inwards towards
the junction of the inner and anterior walls of the middle ear, that is
to say, towards the tympanic orifice of the Eustachian tube. The
membrana tympani undergoes a variable degree of destruction. In the
lesser cases the membrane is torn in its upper and front part only--in
the region of the membrane of Shrapnell--whilst in the more serious
cases it may be completely destroyed. The blood that escapes from the
ear is derived from those vessels that supply the lining cuticle of the
external and middle ears, from the numerous tympanic vessels, from the
lateral sinus, and from the middle meningeal artery. The amount of blood
which escapes varies according to the source of the hæmorrhage. When
hæmorrhage occurs from the smaller vessels, the blood either clots in
the external meatus or trickles from the ear. In the most severe cases
the hæmorrhage is profuse and long-continued. Some years ago a case
came under my observation that threw light on the probable source of
such severe hæmorrhages.

  A man was admitted into the hospital, suffering from profuse
  hæmorrhage from the ear as the result of a fall down an area. The
  bleeding continued for fourteen hours, soaking the dressings and
  continuing so long as the man lived. At the post-mortem examination an
  extensive comminution of the tegmen tympani was discovered, the
  fracture being associated with great extra-dural extravasation of
  blood from a lacerated middle meningeal artery. The extra-dural
  hæmorrhage was enabled to escape through the tegmen tympani into the
  middle ear, and thence by means of the lacerated membrana tympani (see
  Fig. 38).

Profuse and long-continued hæmorrhage from the ear should always arouse
suspicion as to the possibility of injury to the middle meningeal
artery. Since meeting the case recounted above, many similar cases have
come under my care, and, in several instances, guided by this symptom
alone, operative measures have been carried out successfully.

The two following cases show, however, that the extra-dural
extravasation may be derived not only from the middle meningeal artery
but also from the lateral sinus.

  ‘A man fell down an area and suffered from continuous hæmorrhage from
  the ear. He remained in bed for a few days, and then, becoming tired
  of confinement, got up, walked some distance on a cold and frosty day,
  and visited a _sage femme_. On returning home he complained of feeling
  ill, the hæmorrhage from the ear ceased, and shortly afterwards he
  became unconscious and died. The autopsy showed an extensive fracture
  of the petrous bone with extensive extra-dural hæmorrhage from a torn
  lateral sinus and from a lacerated meningeal artery.’[18]

  The man had remained fairly well so long as the extra-dural blood was
  permitted a free means of escape through the tegmen tympani and
  external auditory meatus, but, so soon as clotting occurred,
  compression symptoms developed and the man died in that condition.

  ‘A man, 50 years of age, fell down, striking his head against the
  kerb. On admission it was seen that blood was trickling freely through
  a torn membrana tympani. He rapidly became unconscious and died. The
  post-mortem examination revealed a fracture involving the middle ear
  and external auditory meatus, passing backwards across the lateral
  sinus, in which region there was a large extra-dural extravasation of
  blood.’[19]

The above statements are confirmed by Dwight,[20] who, in 146 autopsies,
found that, in 69 per cent. cases of fracture of the middle fossa of the
skull, there was bleeding from the ear, and that in 29 per cent. cases
the fracture was associated with laceration of branches of the middle
meningeal artery.

Although hæmorrhage from the external auditory meatus may be regarded as
almost diagnostic of a middle fossa fracture, especially of that variety
previously described as the ‘typical basic fracture’, yet the blood may
be derived from a torn membrana tympani or from laceration of the lining
cuticle of the external meatus. Aural examination will soon prove
whether the blood is coming through a rent in the membrane, in which
case the diagnosis is clear. Sometimes bleeding takes place from both
ears, a symptom practically diagnostic of the transverse middle fossa
fracture known as the ‘typical basic fracture’.

The following statistics will supply further information as to the
relative frequency with which hæmorrhage occurs from ears, nose, and
mouth, and the proportionate mortality. The cases were collected and
tabulated by Crandon and Wilson.

  -------------------------+--------+--------+-------+-------------
                           |_Cases._|_Lived._|_Died._|_Mortality._
  -------------------------+--------+--------+-------+-------------
  Hæmorrhage from the ear  |   281  |   170  |  111  | 39 per cent.
  Hæmorrhage from both ears|    47  |    16  |   31  | 66 per cent.
  Hæmorrhage from the nose |    44  |    17  |   27  | 61 per cent.
  Hæmorrhage from the mouth|   168  |    73  |   93  | 33 per cent.
  -------------------------+--------+--------+-------+-------------


_Special points in prognosis and treatment._ It is not possible to
formulate any very definite prognosis when the hæmorrhage takes place
from one ear only, though the mortality is about 40 per cent. When
bleeding takes place from both ears the outlook is more grave, the
mortality being about 66 per cent.

With regard to special treatment, two points are obvious: (1) that
syringing of the ear is absolutely contra-indicated, on the ground that
such treatment carries with it a considerable risk of bringing about
meningeal infection; and (2) that plugging the external meatus with
strips of gauze is an unsurgical form of treatment, insomuch as the
escape of blood from the ear is an important factor in preventing
compression of the brain, more especially in those cases where
hæmorrhage is profuse. Under the last named conditions, operative
measures--exploration for a torn meningeal artery or lacerated venous
sinus--are to be carried out.

Hæmorrhage from the mouth may be slight or copious, according to the
source from which the blood is derived. In the former case, the bleeding
takes place from sphenoidal and pharyngeal vessels, in the latter from
the cavernous sinus or from the internal carotid artery (see p. 148),
the bone being shattered in the region of the sphenoidal body, with
comminution of the walls of the contained air-sinus.


=Escape of cerebro-spinal fluid.= This condition was first investigated
by Van der Wiel in 1727, and more completely by Langier in 1839. The
majority of those middle fossa fractures which involve the petrous
portion of the temporal bone pass immediately anterior to the genu of
the facial nerve (see p. 102), and it follows, therefore, that the
fracture cannot so involve the dural and arachnoid prolongations of that
nerve in such a manner as to allow of the escape of cerebro-spinal
fluid. This fact probably explains another fact, namely, that aural
cerebro-spinal discharge is an infrequent symptom in middle fossa
fractures. On the other hand, as a result of blows applied to the
occipital region, a fracture originating in the posterior fossa may cut
across the petrous bone, almost at right angles, in such a manner as to
sever the seventh nerve in the region of the genu (see Fig. 41). This is
the usual nature of a basic fracture associated with the escape of
cerebro-spinal fluid from the external auditory meatus. More rarely,
this particular class of fracture is unaccompanied by any injury to the
tympanic membrane, in which case the fluid may escape along the
Eustachian tube into the nose and naso-pharynx (see p. 91).
Cerebro-spinal fluid may also escape from the nose and mouth in middle
fossa fractures in the event of extensive injury to the basi-sphenoid
with involvement of the overlying cisterna basalis. The following case
exemplifies that condition:--

  A man suffered from a severe fracture of the middle fossa. Three weeks
  later there was a sudden and profuse discharge of cerebro-spinal fluid
  from the nose. Meningitis developed and the patient died. The
  basi-sphenoid was extensively comminuted, the overlying membranes
  torn, whilst a probe could be passed readily from the cranial cavity
  into the naso-pharynx.


_Special points in prognosis and treatment._ The question of
cerebro-spinal discharges has been discussed previously (see p. 91). It
is therefore merely necessary to lay further stress on the fact that
syringing of the ear is absolutely contra-indicated, for reasons already
stated. The ear should be cleaned out with wool and gauze and _lightly_
packed with strips of gauze, these to be renewed when soaked with fluid.
When the cerebro-spinal discharge is long continued, acute eczema of the
side of the neck may develop as a result of the irritating effect of the
fluid. Under these circumstances it is advisable to adopt precautionary
measures, painting the skin with ‘new skin’ or collodion. Ointments are
of but little use. The eczema will clear up so soon as the discharge
ceases.


=Escape of brain-matter.= The conditions needful for the discharge of
brain-matter from ear or nose have been enumerated previously (see p.
93). There are but few cases recorded in literature, and one case only
has come under my own observation:--

  A lad, 11 years of age, fell some distance out of window on to his
  head. He was admitted under the care of my colleague, Mr. Lockwood. On
  admission he was unconscious, and was bleeding freely from the right
  ear and nose. Shortly afterwards it was noticed that brain-matter was
  issuing from the right external auditory meatus, sufficient
  brain-matter being obtained to fill a teaspoon. The extensive nature
  of the brain-injury was confirmed by the fact that the left arm and
  leg were paralysed for some days. On the fourth day the boy regained
  consciousness and recognized his relations. From this period onwards
  he made an uninterrupted recovery. I have seen the lad on various
  occasions, the last time one year after the accident. At that time he
  was an exceedingly bright and intellectual boy.

_Special points in treatment and prognosis._ The brain-matter should be
gently wiped away from the ear, and the meatus cleansed and lightly
plugged with gauze. Operative measures are required in the event of the
development of symptoms pointing to brain compression. The prognosis
must necessarily be unfavourable, but, as the conditions are almost
entirely confined to the young, the most astonishing recoveries are
reported.


=Involvement of nerves.= The second and third divisions of the fifth
nerve pass respectively through the foramen ovale and the foramen
rotundum, two foramina which lie anterior to the petro-sphenoidal
suture, a suture traversed by the majority of middle fossa fractures.
These two nerves are therefore seldom involved.

In all the cases of fractured base which have come under my observation
I have never seen the foramen rotundum implicated, and in one case only
was the foramen ovale involved.

In certain rare instances, a fracture, passing in the antero-posterior
direction, may cut across the apex of the petrous bone in close relation
to the cavum Meckelii--the bed of the Gasserian ganglion--in which case
all three terminal divisions of the fifth nerve may suffer. Thus, a
case was reported by Lee in 1853 in which, seven weeks after the
accident, the following symptoms were present:--anæsthesia of the left
face and forehead, anterior two-thirds of tongue, and left nostril,
together with weakness of the left masticating muscles, and an opaque
left cornea.


_The sixth nerve._ The sixth nerve may be involved either by itself or
in conjunction with other cranial nerves. In the latter case the paresis
is due to blood extravasated in the sphenoidal fissure or in the orbital
cavity. In the former case the nerve is injured where it grooves the
lateral aspect of the dorsum ephipii, a process frequently fractured in
lesions of the middle fossa. Fractures tend to pass obliquely across
this process, one nerve usually escaping. The prognosis as to functional
recovery is very problematical.


_The seventh and eighth nerves._ There can be no doubt that the seventh
nerve, on account of its complicated intrapetrous course, is more
frequently involved than any other cranial nerve. Köhler records 22
cases in 48 middle fossa fractures. My own experience coincides closely
with Köhler’s, facial paresis or paralysis being noted in nearly 50 per
cent. cases of middle fossa fracture.

The question of facial nerve implication is so intimately associated
with involvement of the eighth nerve that the two subjects must be
considered together. Thus, cases may be classified as follows:--

  1. Cases of paresis of the facial nerve with a variable degree of
  deafness.

  2. Cases of complete facial paralysis with complete deafness.

The greater number of middle fossa fractures involve the middle and
external ears, as is evidenced, amongst other symptoms, by hæmorrhage
from the ear. Some degree of facial paralysis is frequently existent,
not always evident at first sight, but requiring careful examination and
comparison between the two sides of the face. The fracture involves both
roof and floor of the external ear and passes inwards towards the
junction of anterior and inner walls of the middle ear, the membrana
tympani undergoing a variable degree of destruction whilst the ossicles
may also be injured. Thence, the fracture passes inwards towards the
petro-sphenoidal suture in such a manner that the geniculate ganglion
of the facial nerve is exposed and laid bare on the anterior aspect of
the posterior portion of the skull.

The facial nerve, therefore, escapes direct injury except in so far that
the ganglion may be compressed by blood-clot or fragments of bone.
Partial loss of function results. In most cases the blood is absorbed
and a complete recovery may be anticipated. The degree of deafness is
directly proportionate to the damage incurred by the membrana tympani
and ossicles.

[Illustration: FIG. 39. TO SHOW THE RELATION OF A TYPICAL BASIC FRACTURE
TO THE MIDDLE EAR AND ITS ADJUNCTS. A, Malleus; B, Middle ear and
aditus; C, Geniculate ganglion (facial nerve); D, Groove for great
superficial petrosal nerve; E, Canal for tensor tympani muscle; F,
Processus cochleariformis; G, Eustachian tube; H, External auditory
meatus; I, Membrana tympani; J, Mastoid cells.]

In the second group of cases a different picture is obtained. Usually
the result of blows applied to the occipital region, the fracture
traverses the thin cerebellar fossa towards the outer angle of the
jugular foramen, thence cutting across the petrous bone, external to the
internal auditory meatus, and terminating, usually by comminution, in
the tegmen tympani. It is in the transpetrous part of the fracture that
the damage is done, for, not only is the facial nerve cut across in the
region of the ganglion, but the auditory apparatus is also severed into
two parts. The exact line of the fracture is shown in Figs. 40 and 41.

[Illustration: A

B

FIG. 40. TO SHOW THE RELATION OF BASIC FRACTURES TO THE PETROUS BONE. A,
The basic fracture, resulting from a force applied to the left occipital
region, follows the course depicted in Fig. 36. B, The inner half of the
petrous bone, being loose, is thrown forward so as to show the relation
of the fracture to the integral parts of the petrous bone.]

In this class of fracture, though facial paralysis and deafness are both
immediate in onset and permanent in duration, there is, in many cases,
no bleeding from the ear as the membrana tympani may be uninjured.

The facial nerve may also be implicated in that rare type of basic
fracture which was described by Lèon Boullet in 1878, under the title of
‘Fracture of the Mastoid portion of the Temporal bone’. This fracture is
fully described on p. 108. It will suffice to mention that the mastoid
process may be torn away from the base of the skull, the facial nerve
being lacerated as it descends the aqueductus Fallopii.

Bilateral facial paralysis is exceedingly rare. Two cases were described
by the late Professor von Bergmann. Its occurrence is pathognomonic of
the typical basic fracture (see p. 84).

[Illustration: A

B

FIG. 41. TO SHOW THE RELATION OF BASIC FRACTURES TO THE PETROUS BONE. A
shows the course pursued by an antero-posterior fracture of the petrous
bone. Note that it lies external to the internal auditory meatus. B
shows--enlarged--the inner aspect of the outer fragment. Note the
relation of the fracture to the semicircular canals, and that the
membrana tympani and ossicles are quite uninjured.]

_Complete facial paralysis may be associated with the following
symptoms_:--

Epiphora, conjunctivitis, and keratitis (from paralysis of the
orbicularis palpebrarum).

Loss of taste (from involvement of the chorda tympani).

Impaired nasal air-entry (from paralysis of dilator alæ muscle).

Impaired acoustic sensibility (from paralysis of the stapedius).

Impaired mastication (from involvement of the buccinator muscle).

Impaired secretion of saliva (from the cutting off of the secretory and
vaso-dilator fibres of the chorda tympani).

Lastly, it is necessary to add that facial paralysis developing some
days or weeks after the accident, though sometimes dependent on
degeneration of nerve-fibres as the result of pressure in the region of
the geniculate ganglion, may also arise from an ascending neuritis or
from meningeal infection.


SYMPTOMS POINTING TO FRACTURE OF THE POSTERIOR FOSSA


=External hæmorrhages.= In fractures of the posterior fossa, blood
effused into the deeper tissues of the scalp has considerable difficulty
in coming to the surface and thus making itself evident. Furthermore,
the resistance offered by the nuchal muscles tends to confine the blood
to the subtentorial region, thus adding to the already grave prognosis
of fractures in this region. On careful palpation, however, it will be
noted that the nuchal tissues present a doughy or boggy condition,
whilst ecchymosis becomes evident after twenty-four to thirty-six hours.
A peculiar ecchymotic patch is occasionally observed, appearing in front
of the mastoid process and travelling upwards in a curved direction,
concavity forwards, following the outline of the ear. It is said to
result from the tracking of blood along the course of the posterior
auricular artery. Whether this is the case or not, the hæmorrhage
usually implies a separation along the line of the masto-occipital
suture.

  =Escape of cerebro-spinal fluid.=  } Neither of these symptoms
  =Escape of brain-matter.=          }        are present.


=Involvement of nerves.= When dealing with fractures of the middle
fossa, allusion was made to the implication of the seventh and eighth
pair of nerves as the result of a fracture traversing the posterior
fossa of the skull towards the outer angle of the jugular foramen and
cutting across the petrous bone (see p. 104).

The ninth, tenth, and eleventh cranial nerves may be injured in the same
variety of fracture. These three nerves are, however, so protected by
their dural sheaths that they generally escape injury.[21]

In the following cases the nerves were involved:--

  The patient was admitted suffering from a fracture resulting from a
  blow on the posterior parietal region. During the next four days no
  special symptoms developed. On the fifth day, during a sudden attack
  of dyspnœa and dysphagia, death occurred. A fissured fracture was
  found which extended into the jugular foramen, a region occupied by
  blood-clot.

  A man committed suicide by means of a pistol-bullet fired through the
  mouth. The bullet lodged against the under surface of the petrous
  bone, tearing the jugular vein and lacerating the nerves passing
  through that foramen.

  In another case the patient was admitted with a fractured base. He
  progressed favourably until the tenth day when, on sitting up suddenly
  in bed, he was seized with rigors, dyspnœa, and dysphagia, dying
  shortly afterwards. A basic fracture was found, practically dividing
  the skull into two parts and involving the jugular foramen.
  Displacement had occurred with consequent compression of the ninth,
  tenth, and eleventh nerves.


_The twelfth nerve._ The anterior condyloid foramen is most favourably
situated with respect to the course pursued by posterior fossa
fractures. No instance of its involvement has come under my own
observation.

Stierlein records a case in which the tenth and twelfth nerves were
injured, with inability to speak or swallow, paralysis of the right half
of the tongue, soft palate, vocal cords and pharyngeal constrictions.
Death resulted in seven weeks.

The late Professor von Bergmann[22] mentions a case of hypoglossal
paralysis together with paralysis of the sterno-mastoid and trapezius
muscles (eleventh nerve).

For _treatment_ of basic fractures, see p. 116.

FRACTURE OF THE BASE OF THE SKULL: SUMMARY OF SYMPTOMS

  ----------------------+----------------------+----------------------
    _Anterior Fossa._   |   _Middle Fossa._    | _Posterior Fossa._
  ----------------------+----------------------+----------------------
  _Hæmorrhages._        | _Hæmorrhages._       | _Hæmorrhages._
    Subconjunctival.    |   Into the temporal  |   Into the nuchal
    Palpebral.          |   region.            |   region.
    Peripalpebral.      |   From the mouth.    |   Into the occipital
    Orbital.            |   From the nose.     |   region.
    Retinal.            |   From the ear.      |   Into the
    From the nose.      |                      |   post-auricular
    From the mouth.     |                      |   region.
                        |                      |
  _Cerebro-spinal       | _Cerebro-spinal      | _Cerebro-spinal
  fluid._               | fluid._              | fluid._
    From the nose.      |   From the nose.     |   None.
    From the mouth.     |   From the mouth.    |
                        |   From the ear.      |
                        |                      |
  _Brain-matter._       | _Brain-matter._      | _Brain-matter._
    From the nose.      |   From the ear.      |   None.
                        |                      |
  _Air-escape._         | _Air-escape._        | _Air-escape._
    From the frontal    |   From the mastoid   |   From the mastoid
    sinus.              |   antrum.            |   antrum.
    From the ethmoidal  |                      |
    cells.              |                      |
                        |                      |
  _Nerve-involvement._  | _Nerve-involvement._ | _Nerve-involvement._
    Olfactory.          |   Fifth (second and  |   Seventh.
    Optic.              |   third divisions).  |   Eighth.
    Third.              |   Sixth.             |   Ninth.
    Fourth.             |   Seventh.           |   Tenth.
    Fifth (first        |   Eighth.            |   Eleventh.
    division).          |                      |   Twelfth (?).
    Sixth.              |                      |
  ----------------------+----------------------+----------------------


FRACTURE OF THE MASTOID PORTION OF THE TEMPORAL BONE

Fractures limited to this region are of rare occurrence. Our knowledge
of the condition is obtained from the researches of Lèon Boullet, who
first described the fracture in 1876, reporting at the same time 26
cases.

The fracture usually results from sharp blows delivered along the
posterior border of the mastoid process, the force acting obliquely from
above downwards and forwards. More rarely, the process is detached as
the result of a blow delivered immediately above the ear, that organ
sharing in the displacement. In either case the detachment is usually of
an incomplete nature, mainly on account of the muscular and pericranial
attachments in the region involved.

According to Boullet, the following symptoms result:--


=Surgical emphysema and pneumatocele.= Air escapes from the mastoid
cells and antrum into the overlying tissues, either spreading widely
through the subaponeurotic space of the scalp and cellular tissues of
the neck (surgical emphysema), or remaining localized and forming a
tumour of inconsiderable size (pneumatocele). In either case palpation
reveals that peculiar crepitation which is pathognomonic of tumours of
this nature.


=Bleeding from the ear.= Hæmorrhage takes place into the middle ear,
and, as the tympanic membrane is usually lacerated, the blood escapes
from the external ear. In the event of the tympanic membrane being
uninjured, the blood may escape along the Eustachian tube into the
naso-pharynx.

Boullet also pointed out that certain complications may be associated
with the mastoid lesion. These are as follows:--

        _Immediate._                        _Remote._

  Wound of the lateral sinus.        Deafness.
  Laceration of dura and brain.      Otitis media.
  Injury to the aqueductus Fallopii  Caries and necrosis of the
  and paralysis of the               petrous bone.
  seventh nerve.


=Treatment.= The displacement of the mastoid process is of so incomplete
a nature that the question of replacement by open operation seldom
arises. In the event, however, of intracranial complications, operative
treatment must be carried out. Under ordinary circumstances the
treatment consists mainly in the prevention of suppuration. When
suppuration occurs, frequent cleansing of the ear must be carried out in
order to prevent accumulation of pus in middle ear and antrum. This
object is to be attained, not by syringing, but by gentle irrigation and
light packing. Later on it may become necessary to carry out the
complete mastoid operation.


FRACTURES OF THE VAULT OF THE SKULL

Fractures of the vault of the skull may be restricted to the vault or
associated with a basic fracture. Evidence has been brought forward
previously to show that many vault fractures may be regarded as mere
upward extension from a primary basic lesion. The limitation of a
fracture to the vault depends on the nature of the productive force, the
degree of violence used, the site of application, and the direction of
the force. Thus, the smaller the weapon, the greater the violence, the
nearer the site of application to the vertex, the more direct the blow,
the greater is the tendency to vault limitation. Again, compound
fractures are much more liable to vault limitation than simple
fractures, as is proved, for instance, by the reports of Sir Prescott
Hewitt--20 compound fractures in which the fracture was restricted to
the vault of the skull, and 56 simple fractures in which the base was
involved in all but one.

Fractures of the vault may involve:--

  (_a_) the external table only;

  (_b_) the internal table alone;

  (_c_) the whole thickness of the skull.


=Fractures of the external table alone.= These fractures are excessively
rare. Their existence was even doubted till the recent South African
War, when Makins[23] saw one case of this nature. They appear to be due
to the impact of a glancing bullet (see p. 297). A ‘gutter-shaped’
depression results, the comminuted fragments of the external table being
carried away or distributed in the region of the lacerated scalp (see
Chapter IX).


=Fractures of the internal table alone.= Ambrose Paré drew attention to
this class of fracture in 1652, but it remained for Teevan to
investigate more fully the condition in 1865. Previous to Teevan’s
investigations, it had been considered that the internal table of the
skull was the more brittle, and that fractures confined to the internal
table were to be explained on that hypothesis. Teevan, however,
demonstrated the incorrectness of such a theory, for, on firing bullets
through the skull, from without inwards and from within outwards, it was
found that on all occasions the more distal table suffered the more
severely. This was explained in the following manner:--the fracture of
the proximal table was produced by the bullet, whilst that of the distal
table resulted, not from the passage of the bullet alone, but also from
various fragments of bone driven along with the bullet.

Teevan’s experiments also proved that a fracture of the internal table
alone could be produced mechanically, this being in obedience to the law
that ‘when a pressure is applied to a body the fracture commences on the
line of extension, not that of compression’.

Fractures of the internal table are undoubtedly more common in those
situations where diploic tissue is prevalent, e.g. in the frontal,
parietal, and upper occipital regions. In the squamo-temporal and
cerebellar regions fractures of the internal table are almost unknown.

Teevan also stated that ‘but little force is required to produce such a
fracture, and that they are produced usually by some small body, such as
a stone’.


=Fractures involving the whole thickness of the skull.= Fractures which
involve the whole thickness of the skull may be:--

(_a_) Simple or compound.

(_b_) With or without depression.

  When depressed, the fragments of bone may be either loose or
  interlocked, forming in the latter case the so-called pond and gutter
  fractures.

(_c_) Elevated, usually from sabre-cuts.

(_d_) Fissured, stellate, comminuted, punctured, &c.

(_e_) Explosive.


=Symptoms associated with fracture of the vault.= A diagnosis of
fracture of the vault is made:--

On the evidence obtained by local examination.

On the evidence supplied by symptoms dependent on injury to the
intracranial contents.

The various intracranial lesions are discussed elsewhere (see Chapters
III and IV).


=Evidence supplied by local examination.= A compound fracture will be
most readily determined by digital examination, previous to which the
scalp-wound must be carefully cleansed. Digital examination is greatly
preferable to investigation with the aid of the probe. In any case care
must be taken to avoid mistaking one of the sutures of the skull for a
fissured fracture.

In simple fractures the diagnosis is frequently obscured by an extensive
subaponeurotic or subpericranial hæmatoma. Irregularities of surface are
more or less diagnostic of a solution in the surface of the bone, and a
linear hæmatoma is of corresponding clinical value. In any case, the
presence of an extensive hæmatoma must be regarded as of so suggestive a
nature that exploration is called for, more especially when prolonged
concussion or compression are co-existent. Such treatment is imperative
when the hæmatoma--whether diffuse, localized, or linear--pulsates, such
a condition implying a breach in the surface of both bone and dura with
communication between the extra-cranial and some intra-cranial
hæmorrhage.

Pringle[24] lays stress on the value of percussion as an aid to
diagnosis.

  ‘The patient’s head must be supported beneath the occiput, the mouth
  either open or shut--it matters not, so long as it is the same
  throughout the examination--and the skull is struck sharply with the
  finger. When a fracture is present, two changes in note may be
  elicited. Either a note lowered in pitch over the fracture zone, or,
  in addition, a definite crack-pot sound. The note elicited is most
  typical when comminution is present, and some fragments loose. A
  fracture of a T or L or V-shape gives the best crack-pot sound, and
  the crack quality is always most pronounced when the percussing finger
  comes over the angular portion of the bone. Hæmorrhage into the
  subaponeurotic region blurs the note.’

[Illustration: FIG. 42. A COMMINUTED FRACTURE OF THE SKULL.]

If time and occasion permit, an X-ray photograph will clinch the matter.

When the fracture involves the internal table alone, the symptoms are
less definite. Teevan stated that this class of fracture does not lead
to the development of any symptoms unless:--

The middle meningeal artery be injured.

The dura mater and brain be irritated.

The brain be compressed.

He also adds that the existence of the following features suggests the
nature of the injury:--

  The history of a slight blow, probably with a small body.

  The blow situated over the parietal region.

[Illustration: A

B

FIG. 43. AN EXPLOSIVE FRACTURE OF THE VAULT OF THE SKULL. A shows the
right side of the skull and the site of entry of the bullet. B shows the
extension of the fracture round the left half of the skull. In the left
upper parietal region (Fig. B) a fissured fracture is seen where the
bullet failed to perforate the skull.]

  Chronic fixed pain, some days or weeks afterwards, with symptoms of
  brain-irritation or encephalitis, and even suppuration, suggesting
  irritation of the meninges and brain by spicules of bone.

  Compression and paralysis on the opposite side of the body some hours
  afterwards, as the result of injury to the middle meningeal artery.

  Symptoms of compression early and slight, combined with partial
  paralysis of the opposite side of the body.

  ‘The less definite the symptoms of compression, the greater the reason
  to believe that they are caused by the internal table only.’

Before entering into the question of _treatment_ of fractures of the
skull, it is essential that allusion should be made to the _temperature
in its relation to head-injuries._ The great importance of temperature
changes in the consideration of operative treatment will be manifest
when discussing the treatment of fractures of the base.


=The temperature in its relation to head-injuries.= The various
temperature changes observed in cases of head-injury have afforded a
subject prolific in discussion. Broca, Battle, Guyon, Walsham, and
others have endeavoured to deduce facts from the examination of head
cases, but the results have been rather indefinite. In over 300 cases
that have come under my observation, accurate records of the temperature
charts were obtained, the patients were watched throughout their
illness, and in the case of death, the autopsies were attended.

The following deductions were made:--

1. That, for a variable period of time after the injury, the temperature
is always subnormal--sometimes so low that it cannot be registered. This
is the period of shock.

2. That the patient may die in this state of shock, but that, if he
lives, reaction takes place and the temperature rises.

3. That this rise in temperature is, in fatal cases, rapid and
progressive. In one case the temperature rose 6° in seven hours, in
another 8° in four hours. Death occurs when the temperature is at its
highest--anything up to 106°, and even more when registered in the
rectum.

4. That the temperature may rise to a moderate height, and there ‘mark
time’. This is the ‘crisis’ of the case. A subsequent fall in
temperature generally indicates recovery, a further rise usually points
to a fatal termination.

5. That the rise of temperature is independent of any special osseous
lesion, since similar changes are observed in fractures of the vault and
in fractures of the base.

6. That laceration of the brain is present in the majority of cases in
which marked temperature changes are observed, but that the changes in
temperature are totally independent of any special regional
brain-injury.

Richet arrives at the conclusion that two hypotheses present themselves,
accounting for temperature changes in general: (1) that there are
certain temperature regulators in the encephalon which, when excited,
become stimulated in function; (2) that the cortical injury acts in a
sort of reflex manner on the regulatory centres situated in the pons or
bulb.

Attention was also drawn to the experiments of Lorin and van Benedin,
who, after excising the two cerebral hemispheres of a pigeon, showed
that the heat regulatory centre was preserved intact, proving that the
corpus striatum is not necessarily the head-office for heat-regulation
in general.

Till, therefore, more evidence comes to hand with respect to
heat-regulation in general, one cannot go beyond the broad statement
that, in severe head-injuries, definite temperature changes occur, that
the changes are independent of any special lesion of bone or brain, that
they are generally associated with some brain-injury, and that they are
probably due to the influence exerted by the lesion on the
heat-regulating centres in the region of the pons and bulb.

With regard to the value of the temperature, both with respect to
prognosis and treatment, a very much more definite statement can be
made.

First with respect to the =prognosis=. All cases of head-injury may be
grouped into four classes, according to the changes of temperature
present.

_Group 1._ The temperature, at first subnormal, undergoes a rapid and
progressive rise. Prognosis most unfavourable.

_Group 2._ The temperature, at first subnormal, rises gradually to 101°
or 102° and there ‘marks time’. This hesitancy marks the crisis of the
case, further elevation indicating a fatal result, whilst a fall offers
every hope of recovery.

_Group 3._ The temperature, at first subnormal, rises to normal and
remains at that level. Prognosis very favourable.

_Group 4._ The temperature, at first subnormal, remains subnormal. The
condition of shock persists, and the prognosis is most unfavourable.

Practically all cases of head-injury fall readily into one or other of
these four groups, and the temperature chart presents so clear a picture
that it must be regarded as of the greatest possible value in estimating
the prognosis in any given case. In other words, the temperature chart
affords an almost infallible guide both to prognosis and treatment.

With respect to alteration in temperature on the two sides of the body,
the clinical value of such changes must, from my own observations, be
regarded as of a very indefinite nature.

It now remains to discuss the value of temperature changes with respect
to treatment.


=Treatment of Fracture of the Base of the Skull.= In the earlier
paragraphs of this chapter the special treatment of aural and nasal
hæmorrhages and cerebro-spinal discharge was discussed, and some
allusion was made to the necessity of exploring the middle fossa in
cases of profuse arterial or venous aural bleeding. The general
treatment of basic fractures now requires description, previous to
which, however, space must be made for a short account of the routine
treatment by Urotropin--as advised by Crowe and Cushing--as a
prophylactic against the development of meningeal infection. The
following is a summary of Crowe’s paper[25] on the ‘excretion of
Urotropin in the cerebro-spinal fluid and its therapeutic value in
meningitis’.

1. Urotropin, when given by the mouth, invariably appears in the
cerebro-spinal fluid.

2. The largest amount of Urotropin is present in the cerebro-spinal
fluid from thirty minutes to an hour after the ingestion of the drug.

3. After doses of Urotropin, within therapeutic limits, a sufficient
amount of the drug appears in the cerebro-spinal fluid to exercise a
decided inhibitory effect on the growth of organisms inoculated into
this fluid after its removal from the body.

4. Following a subdural inoculation of dogs and rabbits with
streptococcus, 60-80 grains of Urotropin a day, given under conditions
which insure absorption, will markedly defer, and in some cases prevent,
the onset of a fatal meningitis.

5. In view of these observations, the prompt administration of Urotropin
is advised in all clinical cases in which meningitis is a possible or
threatened complication, or even when meningeal infection has actually
occurred.

[Illustration: FIG. 44. A TEMPERATURE CHART ILLUSTRATING THE CHANGES IN
TEMPERATURE OBSERVED IN HEAD-INJURIES.

(For description, see text.)]

Acting on these suggestions, I am accustomed to treat all head cases
with this drug, 10-20 grains three times a day by mouth. It may be given
per rectum, though probably with less satisfactory results. Traumatic
cases are treated as soon as possible, other cases receive their dose
for two or three days previous to the operation, the drug being
continued till all fear of possible meningeal infection has vanished.

In discussing the general treatment of basic fractures, it must be
accepted that the basic fracture in itself requires no treatment. Danger
or death is dependent on intracranial complications, and an
uncomplicated basic fracture demands no active surgical treatment. The
special treatment applicable to cases complicated by hæmorrhages, both
external to and beneath the dura mater, is discussed in the next
chapter. It is therefore only necessary to enter into those cases of
fractured base which are associated with concussion, irritation, and
compression of the brain--in other words, the _average_ case of fracture
of the base of the skull.

The surgeon must always be guided by the general condition of the
patient--the blood-pressure, character of pulse, state of respiration,
depth of unconsciousness, &c.--but, in my opinion, the temperature chart
affords perhaps the most valuable basis on which rules can be formulated
guiding the surgeon in his general line of treatment.

Thus (1) =when the temperature remains subnormal= the patient is in a
condition of severe cerebral shock, due, in the majority of cases, to
contusion or laceration of the brain, the grosser lesion being most
commonly situated either at the apex of the temporo-sphenoidal lobe or
at the anterior inferior part of the frontal lobe. The patient is,
however, suffering from shock, and the treatment advocated for that
condition in general is equally applicable to these cases in particular.
The patient should be placed in the so-called head-down position, and
the extremities firmly bandaged from below upwards. The vaso-motor
depression should be combated by the administration of rectal or
intra-venous infusions of saline solution, to each pint of which is
added 1 drachm of a 1 in 1,000 solution of Adrenalin Chloride. It is at
once obvious that, whilst combating the condition of shock, this mode of
treatment may tend at the same time to encourage fresh bleeding if the
brain should have been lacerated, or if intracranial vessels should
have been torn. For this reason I regard rectal infusion as the more
safe of the two methods, in spite of the fact that intra-venous infusion
brings about a more rapid improvement in the patient’s condition. The
effect of the infusion must be carefully observed, and as soon as the
blood-pressure rises and the temperature shows a tendency to rise--say
from the subnormal to the normal--the infusion process must be stopped,
and the further progress of the case observed.

The risks attendant on this mode of treatment are obvious, but in their
consideration, it must also be borne in mind that if the patient remains
in the collapse stage, without evidencing any sign of reaction, he will
inevitably die. If the treatment advocated should tide the patient over
this stage and induce a definite reaction, as exemplified by rise of
blood-pressure and elevation of temperature, the further treatment of
the case can be considered under the next group.

(2) =When the temperature rises progressively= the patient evidences
symptoms pointing to compression of the brain--coma, slow pulse, noisy
and stertorous respiration, hot skin and turgid face. Later on, as a
result of the increasing pressure, the medullary centres begin to show
signs of exhaustion, the pulse-rate increasing, and the respiration
becoming Cheyne-Stokes in character.

Whether these symptoms result primarily from the nature of the lesion,
or secondarily after the adoption of those measures advocated for the
collapse stage, it matters not. Our indications with respect to
treatment are clear. The increasing intracranial pressure must be
reduced. This desideratum is preferably carried out by the ligature of a
bleeding meningeal artery, or by the occlusion of a torn venous sinus,
but unfortunately, such a course is frequently out of the question. We
have, therefore, to deal with an increased and increasing intracranial
pressure, without definite localizing features. For this condition we
have at our disposal the following measures: venesection, lumbar
puncture, and ‘decompression’ operations.


=Venesection.= I regard venesection as a valuable means of reducing the
intracranial pressure. It is mainly of use in those cases that hover
between slight compression and the fully-developed condition.
Venesection may therefore be regarded as of special advantage in those
cases that show elevation of temperature to about 101° and there ‘mark
time’. The ‘bleeding’ should be carried out after exposure of the median
basilic, external jugular, or internal saphenous veins, preferably from
the first-named site. The amount of blood to be withdrawn varies
according to the individual circumstances of the case, but, in general,
the escape of blood should be encouraged till the pulse becomes soft,
frequent and compressible. On an average, the quantity of blood
withdrawn varies from 10-20 ounces. The operation not infrequently turns
the scale in favour of the patient. Venesection may also be carried out
in combination with ‘decompression’ operations.

When applied to suitable cases and carried out with discrimination,
venesection often tides the patient over the stage of ‘crisis’. The most
careful observation is needed in estimating the quantity of blood to be
withdrawn, the pulse, blood-pressure, respiration, and temperature
affording an adequate guide.


_Lumbar puncture._ In spite of the apparent advantages of this method,
it must, I think, be acknowledged that lumbar puncture is of but little
use in reducing the general intracranial pressure. Consequently, in
spite of the fact that this procedure has been strongly recommended,
experience shows that it is of little practical use. This statement,
based on personal experience, is at variance with the opinion of some
other surgeons. For instance, de Quènu reports 7 cases of fractured
skull which were ‘cured’ by this treatment, one of them requiring to be
punctured eight times. Lumbar puncture assists the diagnosis, but I am
doubtful whether it improves the prognosis.


_‘Decompression’ operations._ ‘Decompression’ operations may be carried
out over the cerebellar fossa or over the temporal region of the skull.
In =cerebellar decompression= a suitable scalp-flap is turned down and
the trephine applied over the centre of the exposed occipital bone.
After the removal of the disk the wall of the cerebellar fossa is cut
away with the craniectomy forceps, up to the line of the lateral sinus
above, to the mastoid process in front, to the vicinity of the foramen
magnum below, and almost up to the middle line on the inner side. The
bulging dura mater is incised in a crucial manner, right up to the
margins of the osseous gap, all meningeal vessels that cross the line
proposed for dural section being under-run with a fully-curved needle
threaded with catgut. A small drainage-tube is inserted between the dura
and the cerebellum and brought out through the most dependent part of
the scalp-flap. The flap is then sutured in position. The drainage-tube
should be stitched to the skin and withdrawn twenty-four to forty-eight
hours later, according to the progress of the case.

I have carried out this operation on several occasions, but in spite of
some immediate improvement in the condition of the patient, the remote
results have been so unsatisfactory that I have abandoned the operation
entirely. The effect of this cerebellar decompression is too radical,
the medullary centres strongly object to such heroic attempts at
pressure relief.

_Temporal_ decompression, more correctly known as the
=intermusculo-temporal decompression= operation of Harvey Cushing, leads
to very different results. Previous to dealing with the technique of the
operation, it will be convenient to enumerate the advantages claimed for
this method in general.

(1) The frequency with which the bony lesion occurs in the middle fossa
of the skull.

(2) The fact that cerebral contusions are especially liable to involve
the tip of the temporo-sphenoidal lobe.

(3) The exposure of the meningeal territory and the ease of determining
the presence of an extra-dural hæmorrhage.

(4) The possibility of draining through a split muscle rather than
directly through the scalp.

(5) The subsequent protective action of the muscle in case a hernia
tends to form in consequence of traumatic œdema.

(6) The subsequent absence of any deformities, the skin incision being
carried out for the most part through the hairy portion of the scalp.


=The operation.= The hair is shaved over the temporal region, with a
wide margin to the field of operation. In other respects, those
preliminary details should be adopted which are enumerated in Chapter
II. The skin incision commences well above and behind the external
angular frontal process, is directed along the line of, but below the
temporal crest, and curves downwards to terminate just anterior to
the tragus of the ear. Pressure is applied during the formation of the
incision so as to control bleeding from temporal arteries. The flap,
comprising skin, subcutaneous tissue, and superficial temporal artery,
is turned down to a zygomatic base, care being taken to avoid injury to
the temporal vessels at the base of the flap. The temporal fascia is
then incised, parallel to but immediately below the line of the skin
incision, and the fascia also turned down towards the zygoma. The
temporal muscle is split in the direction of its fibres, from the
temporal crest above to the zygoma below, stripped away from the bone
and well retracted in both forward and backward directions. In this
procedure care must be taken to avoid detachment of the muscle-fibres
from the temporal crest. The area of bone exposed, however, should be as
extensive as circumstances permit.

[Illustration: FIG. 45. INTERMUSCULO-TEMPORAL CEREBRAL DECOMPRESSION.
_First stage._ The scalp and temporal fascia have been turned down as
separate flaps. The temporal muscle is divided in the direction of its
fibres, and the exposed bone trephined.]

[Illustration: FIG. 46. INTERMUSCULO-TEMPORAL CEREBRAL DECOMPRESSION.
_Second Stage._ The temporal muscle is retracted on either side, the
bone has been freely cut away, and the bulging dura mater crucially
incised.]

[Illustration: FIG. 47. INTERMUSCULO-TEMPORAL CEREBRAL DECOMPRESSION.
_Third Stage._ The dural flaps are turned aside, exposing the lacerated
temporo-sphenoidal lobe. A rubber drainage-tube has been inserted
beneath the lacerated brain, lying on the floor of the middle fossa of
the skull and brought to the surface through the scalp-flap.]

[Illustration: FIG. 48. INTERMUSCULO-TEMPORAL CEREBRAL DECOMPRESSION.
_Fourth Stage._ The temporal muscle-fibres have been approximated, and
the temporal fascia reunited in part. The drainage tube is seen to
emerge through fascia and scalp.]

The trephine is applied to the bone, the surgeon aiming at the angle
between the anterior and posterior branches of the middle meningeal
artery. The disk is removed, the dura separated from the bone, and the
craniectomy forceps called into requisition, the bone entering into the
formation of the temporal fossa being freely cut away, more especially
in the _downward_, forward, and backward directions--in other words, in
the general line of the temporo-sphenoidal lobe. In the upward direction
the surgeon must be more guarded, more especially when the operation is
being conducted on the left side of the head. Broca’s area of motor
speech must be avoided, for fear of its inclusion in any hernial
protrusion that may ensue.

The bulging and probably discoloured dura mater is freely incised,
preferably in a crucial manner, though the exact line of such incision
is of little importance so long as it is free in character. Needless to
say, all meningeal vessels that cross the lines proposed for dural
section must first be ligatured (by underrunning with a fully curved
needle) on either side of those lines. The four dural flaps are turned
aside and the antero-external aspect of the temporo-sphenoidal pole
exposed. A small drainage--or drain of rubber tissue--can now be
inserted along the floor of the middle fossa skull in the immediate
vicinity of any lacerated brain or blood-clot, the drain lying between
the dura and the brain, and anchored to the dura mater or muscle by a
fine catgut suture.

The four dural flaps are allowed to remain loose over the surface of the
brain, whilst the temporal muscle is sewn across from side to side with
a few catgut sutures, room being allowed at the lower angle for the
emergence of the drain.

The temporal fascia is replaced and carefully united to its upper cut
margin, the drain being brought out through the fascia and through a
puncture hole made at the most convenient part of the scalp-flap. The
scalp-flap is approximated with numerous interrupted silk or salmon-gut
sutures.

The tube is allowed to remain for thirty-six hours or more, according to
the condition of the patient.

The operation may be carried out on one or on both sides of the skull;
if on the one side only, on that side at which laceration of the brain
is probably existent. In connexion with this it is necessary to state
that laceration by contre-coup is more common than direct brain-injury.
Thus, if the blow be inflicted on the right parieto-occipital region,
the operation should be conducted in the left temporal region.

In the absence of all localizing features the decompression should be
carried out on the _right_ side of the head, in order to avoid all
possibility of including, in the hernial protrusion that may result, the
motor speech area of Broca.

In cases of severe head-injury the surgeon must be prepared for many
disappointments, but, from my own experience, it would appear that
Cushing’s operation frequently brings about the most satisfactory
results.

It should, however, be clearly understood that indiscriminate
decompression operations only bring discredit on the method in general.
They should only be carried out in suitable cases.


TREATMENT OF FRACTURES OF THE VAULT OF THE SKULL


=Indications for operation.= It is the general custom to divide
fractures of the vault into two groups--those demanding operative
treatment and those in which an expectant attitude is advised--and
between these two groups a sharp line of demarcation is drawn. There is,
however, no such line of demarcation. In the event of the general
condition of the patient being compatible with operative interference,
such treatment is urgently called for under the following conditions:--

_All_ cases of punctured fracture.

_All_ cases of depressed fracture, whether diagnosed by palpation or by
inference, whether simple or compound, whether complicated or not.

_All_ cases of fracture complicated by extra-dural or localized subdural
extravasation of blood.

_All_ elevated fractures.

_All_ compound fractures.

In all these instances, from the presence of depressed fragments of
bone, from associated injury to the intracranial contents, or from other
causes, no mere expectant policy should be pursued. The surgeon has to
look into the future, to bear in mind the possibility of meningeal
infection, and the more remote results of head-injuries in general (see
Chapter VI). In other words, early and active surgical interference is
imperatively demanded, for not only is it necessary to strain every
endeavour to save the patient’s life, but the surgeon should also adopt
those procedures which guard most effectually against the more remote
possibilities of the case.

With regard to _simple_ fractures, if it can be determined that the
fracture, whether fissured, stellate, or comminuted, is simple and
uncomplicated by any serious intracranial lesion, no active surgical
treatment is required. The determination of such conditions is, however,
quite another matter, always difficult and sometimes, from the presence
of overlying hæmatomata, quite impossible.

In the general estimation of these cases it should be borne in mind that
simple uncomplicated vault fractures are decidedly rare. For instance,
Dwight, in 145 cases of fractured skull that came to autopsy, only found
six that evidenced a fissured fracture localized to the vault. It may,
of course, be urged that these statistics are fallacious, insomuch as
simple uncomplicated vault fractures would probably not come to the
post-mortem table. Clinical evidence, however, coincides with Dwight’s
statistics, and clinical evidence shows, furthermore, that a blow
sufficing to fracture the vault of the skull almost invariably results
in further injury.

In these doubtful cases the surgeon is greatly aided in his decision by
a general review of the patient’s condition, more especially by those
symptoms which are regarded as exemplifying the clinical conditions of
concussion, irritation, and compression.

_When the fracture is associated with mild concussion_ it may be
inferred that the brain is practically uninjured, and that operative
treatment is not required.

_When the fracture is associated with severe concussion_ it may be
inferred that the brain is damaged, to a degree proportionate to the
depth and duration of the stage of unconsciousness. The question of
operation depends to a very large extent on the general condition of the
patient, and more especially on the temperature and temperature changes
(see p. 114). With a persistent subnormal temperature it may be inferred
that the brain-injury is of a very severe nature, and that operative
measures are, for the time being, contra-indicated. In the event of the
temperature rising it may be accepted that the patient is passing from
the state of shock to that of reaction, operative measures again hinging
on the further progress of the case. If the temperature rises
progressively, the patient passing from the stage of reaction to that of
compression, operative measures are indicated. Under other circumstances
an expectant attitude can be adopted.

_When the fracture is associated with general cerebral irritation_ it
may be inferred that the brain is contused or slightly lacerated. Under
these circumstances operation is, for the time being, not required, and
an expectant attitude should be adopted.

_When the fracture is associated with compression_ it may be inferred
that the condition is dependent on depressed fragments of bone, or on
extra- or intra-dural bleeding. Operative measures are now urgently
indicated.

_When the fracture is confined to the internal table_ a diagnosis is
only possible when symptoms of localized irritation ensue, either due to
pressure exercised on the cortex by spicules of bone or resulting from
injury to some intracranial vessel, e. g. the middle meningeal artery.
In such cases operation is indicated. Under other circumstances the
surgeon must await the developments of the case.


=Treatment.= _When the fracture is associated with mild concussion._
During the stage of concussion no active treatment is required, beyond
putting the patient to bed--with the head low--enveloping him in hot
blankets, and applying hot bottles to the extremities. These bottles are
wrapped up in flannel: they should never be placed in contact with the
patient’s skin. As soon as the reaction stage _commences_, the bottles
and blankets should be removed, the patient covered with light clothing
only, and an ice-bag applied to the head, over the region at which the
injury was inflicted. Calomel, in suitable doses, should be given by
mouth, and a copious enema administered per rectum. Perhaps the most
essential point in the general consideration of the case is the
after-treatment. The patient should be kept in hospital or home for at
least one month, and for the next three months or more, according to the
urgency of the case, he should abstain from all mental and bodily work.
At the end of that period of time he may return to work, though still
kept under observation.

_When the fracture is associated with severe concussion._ In the event
of persistence of concussion symptoms of a severe type the prognosis is
decidedly unfavourable. This prolongation of cerebral shock is
undoubtedly dependent in its persistence on severe vaso-motor
depression, and in the majority of cases ending unfavourably it will be
found that the brain is generally œdematous and regionally contused or
lacerated. In cases of this nature the surgeon should confine his
attention, for the time being, to an endeavour at terminating this
vaso-motor depression, raising the blood-pressure and inducing a
definite reaction; the patient being treated after the manner indicated
on p. 118.

_When the fracture is associated with general cerebral irritation._ The
patient should be put to bed in a quiet and darkened room, under the
continuous attention of a trained nurse. An ice-bag or Leiter’s tubes
may be applied to the head, though the patient seldom tolerates such
attentions. I regard morphia as of the greatest service in this class of
cases. It should be given freely, subcutaneously, either by itself or in
combination with atropin. I generally order ¹⁄₄ gr. morphia with ¹⁄₁₀₀
gr. atropin every six hours, till the irritative symptoms subside.

Insomuch as all evidence tends to prove that general cerebral
irritation, as resulting from injury, implies a condition of contusion
or superficial laceration, a prolonged period of bodily and mental rest
is essential before the patient is discharged from treatment and allowed
to return to work--a period of not less than six months.


=The operative treatment of fractures of the vault.= The usual
preparatory treatment is carried out, the scalp-tourniquet applied, a
suitable scalp-flap framed and turned down, advantage being taken of all
existent scalp lacerations.

The subsequent details vary according to the circumstances of the
case:--


=Fissured fractures.= If, after thorough exposure of the parts, the
operator is satisfied that he has to deal with an uncomplicated fissured
fracture, the scalp-flap is accurately sewn into position (see p. 16).
On the other hand, if the symptoms point to the presence of an
extra-dural hæmorrhage, the bone is trephined where the fracture crosses
the line of the suspected vessel and the conditions treated as described
under middle meningeal hæmorrhage. In subdural extravasation the
trephine is applied over that part of the brain, in the immediate
vicinity of the fracture, from which the symptoms appear to emanate, and
the conditions treated as described under subdural hæmorrhage.

In a certain proportion of cases the symptoms point to a marked increase
of intracranial pressure without definite localizing features, a
condition pointing to diffuse subdural hæmorrhage, with or without brain
laceration. Under such circumstances much may be done to relieve the
increased intracranial pressure by carrying out the operation of
‘cerebral decompression’ (see p. 121).


=Depressed fractures.= The operative details vary according to the
nature of the osseous lesion:--

(_a_) If the depressed fragments of bone are so interlocked that
elevation is impossible (e. g. pond and gutter fractures), it will be
necessary to trephine in the immediate vicinity of the depression, in
order to lessen the mutual attachment of the fragments one to another,
so obtaining sufficient purchase for their elevation or removal.

The pericranium is stripped away from the region of the depression (see
Fig. 49), and a small trephine applied in such a manner that the
trephine circle includes the outer part of the depressed area. Care must
be taken to avoid more pressure over the depressed fragments than is
absolutely necessary, for fear of causing further damage to the
underlying structures. This advice is all the more important when it is
realized that the fracture of the internal table is almost invariably
more extensive than that which involves the visible external table of
the skull.

The disk of bone is removed and the conditions investigated with the
dural separator. When the degree of depression and the splintering of
the internal table are not excessive, the parts may be elevated into
position. In most cases, however, the uncertainty that exists with
regard to possible dural injury renders it necessary that the depressed
fragments should be elevated and removed, or so raised as to allow of
adequate inspection of the dura itself. For this purpose the craniectomy
forceps may be required. The dura can now be examined. If torn, the
opening may require enlargement, in order to determine whether any
osseous fragments have been driven into the brain-substance; all such
fragments are carefully removed. Hæmorrhage is arrested, the dura sewn
up, and the scalp-flap carefully sutured. Drainage should always be
avoided, the risk of infection is too great. As a prophylactic against
the development of meningeal infection, the patient should undergo the
routine treatment with urotropin (see p. 116).

(_b_) When the depression is of such a nature that the elevation of the
fragments can be carried out without preliminary trephining, the
fragments are raised with the periosteal separator, and the membranes
and brain examined as described above.

In =simple comminuted fractures= the larger fragments of bone are to be
replaced in the anticipation that they will live entire, in part, or
will act as scaffolding media for the formation of dense fibrous tissue.
After removal from the wound, and during the completion of the
operation, the vitality of all loose fragments may be preserved by
immersion in hot saline solution. All minute fragments of bone should be
discarded.

[Illustration: FIG. 49A. THE ELEVATION OF A DEPRESSED FRACTURE. _First
stage._ The trephine circle includes the outer portion of the depressed
area.]

[Illustration: FIG. 49B. THE ELEVATION OF A DEPRESSED FRACTURE. _Second
stage._ The trephine disk has been removed and the elevator is in
position.]

With respect to =compound= fractures, it is necessary that the bone
lesion should be fully exposed, all pockets of scalp-tissue being slit
up to their termination. Previous to any attempt at examination of the
injured bone, further precautions must be taken to avoid subsequent
infection, by reason of the bruised and soiled scalp. Such tags of
scalp-tissue as appear injured beyond repair should be cut away with the
scissors, and in order to avoid or diminish subsequent wound infection,
I have been accustomed to swab over the most suspicious parts with
pure carbolic acid, washing away the same with saline solution. Since
the advent of iodine sterilization, I have often utilized that solution
in preference to the carbolic, swabbing the whole surface exposed. I
think a combination of the two methods is advisable in more serious
cases, utilizing the carbolic for the margins of the wound and iodine
for the general surface. By means of this method the risk of meningeal
infection and scalp suppuration is greatly reduced. To aid in the
prophylaxis, the patient should again be placed under a course of
treatment by urotropin (see p. 116).

With regard to the bone, all loose fragments should be removed, only
those being preserved which retain their pericranial connexions. Even
these are thrown back so as to permit of the maximum inspection of the
dura mater. This membrane, if torn, is either sewn up at once or opened
up more freely in the investigation and removal of underlying blood-clot
or bone-débris. After removing such troubles the membrane is accurately
sutured. The bone-flaps are now replaced in position. Some surgeons
advocate the replacement of the smaller fragments of bone which have
previously been removed. These fragments may be sterilized by boiling,
but such a process destroys the bone-cells and, in consequence, they
become absorbed, merely acting as scaffolding media for the formation of
fibrous tissue. Added to that, in the event of suppuration, the presence
of such fragments not only leads to the persistence of a purulent
discharge, till the fragments are entirely removed, but also increases
considerably the risk of meningeal infection.

As a summary, therefore, it may be laid down that it is necessary to
remove all loose fragments of bone, the deficiency in the vault being
rectified, if necessary, at a later date by one of the methods
enumerated in Chapter VI.

The scalp-flap is accurately sewn up with interrupted salmon-gut
sutures, a gauze or cigarette drain being inserted at the most
convenient and dependent point, to be removed at the end of forty-eight
hours or more according to the progress of the case.


=Punctured fractures.= Here there is a special liability to dural
laceration and in-driving of comminuted fragments of bone. A full
exposure of the parts is therefore absolutely essential. The trephine
can be applied in the immediate vicinity of the puncture, or, as is
often advisable, in such a manner that the punctured area is included in
the trephine circle: this latter method may necessitate that the
trephining should be carried out without the aid of the guiding
fixation-pin, for which process some experience is needed.

After removal of the bone, the craniectomy forceps may be required, to
allow of adequate dural inspection. The dura mater is opened up with
blunt-pointed scissors, and the brain examined for in-driven fragments
of bone. These, when found, are removed. Deeply situated fragments of
bone and foreign bodies may be previously diagnosed by means of an X-ray
picture.

If possible, both membrane and scalp should be sutured without drainage,
but in the event of possible sepsis, a small cigarette drainage-tube
should be inserted so as to lie beneath the dura mater on the one hand
and emerge through the scalp wound at the other.


=Fractures limited to the external table.= For this class of fracture
the reader is referred to the section dealing with bullet-wounds of the
skull (see p. 296).


=Fractures limited to the internal table.= As previously indicated, the
diagnosis of this condition is only practicable when the depression of
the osseous fragments, or the hæmorrhage resulting from an injured
meningeal vessel, so irritate the dura mater and brain that localizing
symptoms ensue. For instance, epileptic fits of a Jacksonian type may
develop shortly after the accident, this condition demanding a full
exposure of the affected region. The operations required in the
treatment of traumatic epilepsy and intracranial hæmorrhages are
discussed in subsequent chapters.


THE MORTALITY FROM FRACTURE OF THE SKULL

Whatever the nature of the osseous lesion, the mortality is almost
entirely dependent on the question of associated injury to the
intracranial contents, more especially the brain.

In the case of fractures purely or mainly basic, of the cases that have
come under my care or observation, 116 recovered and 89 died--a
mortality of 44 per cent.

Battle, from an examination of 168 cases, puts the mortality at the low
figure of 32 per cent., whilst Crandon and Wilson, from an exhaustive
series of 530 cases, estimates it at 44 per cent.

The mortality varies according to the _age_ of the patient, the
death-rate being at its maximum at the two extremes of life--between 50
and 60 per cent. under the age of 5 years and over 60 per cent. after
the age of 70.

The mortality varies also according to the _fossa_ implicated. Thus, to
each fossa there are certain peculiar dangers--to the _anterior_ fossa,
meningeal infection from the nose, frontal and ethmoidal sinuses; to the
_middle_ fossa, meningeal infection from the naso-pharynx and ear, and
hæmorrhage from the middle meningeal and internal carotid arteries, and
from the cavernous venous sinus; and to the _posterior_ fossa,
laceration of the lateral and sigmoid venous sinuses.

After such consideration of local complications, it would appear that
the middle fossa of the skull presents the greatest dangers. Another
factor must, however, be taken into consideration--injury to the
brain--the commonest cause of death in all head injuries. The main vital
centres are grouped in the region of the fourth ventricle, and Leonard
Hill has proved that any increase in the intracranial pressure exerts
its influence most rapidly and most effectually when the lesion is
situated beneath the tentorium cerebelli.

One may assume, therefore, that fractures of the posterior fossa are the
most dangerous, and that those involving the anterior fossa hold out the
best prognosis.

In the case of pure or primary vault fractures the mortality may be
estimated by reference to the following table. It is composed from 88
cases admitted into St. Bartholomew’s Hospital between the years 1900
and 1906.

  Under the age of  5    8 lived and  2 died. Mortality, 20 per cent.
     „       „     10    2   „    „   3   „      „       60       „
     „       „     15    6   „    „   0   „      „        0       „
     „       „     20   10   „    „   3   „      „       23       „
     „       „     30    9   „    „   1   „      „       10       „
     „       „     40   16   „    „   9   „      „       36       „
     „       „     50    3   „    „   7   „      „       70       „
     „       „     60    2   „    „   1   „      „       33       „
  Over the age of  60    3   „    „   3   „      „       50       „

                        59 lived and 29 died. Mortality, 37 per cent.
                        =============================================

For the remote effects of skull fractures, see Chapter VI.

[17] _Brit. Med. Journ._, September 11, 1909, p. 645.

[18] Chassaignac, _Plans de la Tête_, 1842.

[19] _Milligan, Trans. of the Otolog. Soc._, vol. viii, p. 69.

[20] _Boston City Hosp. Reports_, 1894.

[21] Delfau and Günther narrate a case in which death occurred from
pressure on the tenth nerve. (_Deutsche Klinik_, Berlin, 1853.)

[22] _System of Surgery_, vol. i, p. 93.

[23] _Surgical Experiences in South Africa._

[24] _Edin. Med. Journ._, 1909, p. 526.

[25] _Johns Hopkins Hospital Bulletin_, April, 1909.




CHAPTER V

INTRACRANIAL INJURIES: EXTRA- AND SUB-DURAL HÆMORRHAGES. INJURY TO THE
BRAIN


HÆMORRHAGES


I. Extra-dural hæmorrhage.

Extra-dural hæmorrhage may be arterial or venous in origin. In the
former case the blood is derived almost exclusively from the middle
meningeal artery. When of venous origin the source is usually to be
found in a laceration of one of the sinuses of the brain. When blood is
poured out from a torn sinus it tends to occupy, and be widely diffused
in, the subdural space. A venous extra-dural extravasation is relatively
of infrequent occurrence, and the pressure exercised on the brain seldom
suffices to permit of the development of local or general symptoms of
cerebral compression. On these grounds extra-dural hæmorrhage may be
regarded as almost necessarily of arterial origin, and as derived from a
torn middle meningeal artery.


Middle meningeal hæmorrhage.


_General considerations._ The middle meningeal artery enters the middle
fossa of the skull through the foramen spinosum, and divides, after a
short intracranial course, into two main terminal divisions, anterior
and posterior. The _anterior_ branch passes forwards towards the
anterior inferior angle of the parietal bone, then changing direction
and turning upwards and backwards towards the vertex of the skull. The
_posterior_ branch passes horizontally backwards--grooving the squamous
portion of the temporal bone--towards the posterior inferior angle of
the parietal bone.

Throughout their intracranial course the main trunk and its terminal
branches are embedded in the outer wall of the dura mater, except in the
spheno-parietal region, where the anterior branch of the artery usually
occupies a channel in the bone--one between ¹⁄₂ and 1 inch in extent.

The anterior branch overlies the pre-Rolandic motor area, whilst the
posterior division is related to the temporo-sphenoidal and lower
parietal regions--‘silent’ areas of the brain.

Middle meningeal hæmorrhage occurs most commonly in connexion with a
fissured or comminuted fracture of the temporal region--the result of
direct violence. A fracture, however, is not necessarily present, the
hæmorrhage may take place on the side opposite to that at which the
injury was received (laceration by contre-coup), and both vessels may be
involved. Crisp English narrates three cases in which bilateral
extravasation resulted. These more rare examples of middle meningeal
hæmorrhage are more or less confined to patients suffering from marked
arterial degeneration.

Middle meningeal hæmorrhage, uncomplicated by brain injury, is of
infrequent occurrence, the associated injuries to bone and brain
confusing the diagnosis. Moreover, the special pressure effects are
dependent not only on the absence of serious brain lesion, but also on
the non-existence of a safety-valve, such, for instance, as is afforded
by a comminuted fracture of the bones entering into the formation of the
temporal fossa, or of the roof of the middle and external ears. In the
former case, blood will force its way into the temporal region, there
forming a temporal hæmatoma--one that may pulsate--whilst, in the latter
case, the blood escapes freely from the external auditory meatus. It
should be noted, however, that pressure applied to the temporal hæmatoma
may lead to the development of irritative or paralytic symptoms confined
to the muscles of the opposite side of the body, whilst the restriction
of aural bleeding, by means of plugs inserted into the ear, will lead to
the early development of compression symptoms.

The amount of blood extravasated varies--according to the calibre of the
vessel involved--from a drachm to several ounces. The largest coagulum
that has come under my observation was 4¹⁄₂ inches in the long diameter
and 1 inch in thickness. Krönlein narrates a case in which the clot
weighed 9 ounces.

[Illustration: FIG. 50A. THE INNER ASPECT OF THE SKULL.]

[Illustration: FIG. 50B. THE INNER ASPECT OF THE SKULL SEEN ON
TRANSILLUMINATION.]

In shape the clot is elliptical; in consistency it is either fluid or
jelly-like. During the early stages of its formation it can be readily
removed. Later on, it adheres to the dura mater, and, when removed,
leaves that membrane rough and discoloured.

Some uncertainty exists as to the relative frequency with which the
trunk and the two terminal branches are exposed to injury. There can be
no doubt that the majority of cases in which typical clinical symptoms
are present are such as evidence injury to the anterior terminal
division; this is due to the anatomical relation of the clot to the
motor cortex. Injury to the main trunk is of the rarest occurrence, for
the foramen spinosum lies immediately anterior to the petro-sphenoidal
suture, the course pursued by typical middle fossa fractures. I have
seen one case only, and have read the accounts of two others, in which
the foramen spinosum was directly implicated.

The attachment of the dura mater to the sides and base of the skull
exercises a most important influence on the direction in which the blood
spreads. Firmly adherent to the lesser wing of the sphenoid in front and
to the summit of the petrous bone behind, the membrane intervening
between these two regions is but loosely attached to, and readily
stripped away from, the floor of the middle fossa. As the clot increases
in size it exerts considerable mechanical pressure and tends to separate
still further the dura from the bone. The anterior and posterior
limitations compel the blood to extend first in the outward direction
and then upwards towards the vertex of the skull.

Krönlein divides middle meningeal extravasations, according to their
regional distribution, into three main groups:--

Temporo-parietal (the most common variety).

Parieto-occipital (rare).

Parieto-frontal (very rare).

Middle meningeal hæmorrhages yielding typical clinical symptoms are of
infrequent occurrence, yet such extravasations are very commonly present
in severe lesions of the skull. This is evidenced by the fact that
middle meningeal hæmorrhage--of a greater or lesser degree--was found in
20 per cent. of all cases of fractured skull, and in 45 per cent. of
those in which the middle fossa was involved. My experience is confirmed
by Dwight and Nichols. For example, Dwight, in 149 autopsies, notes that
middle meningeal hæmorrhage was existent in 49 cases (29 per cent.). He
maintains further that the artery is injured in nearly every case in
which the fracture, extending from vault to base or vice versa,
involves the middle fossa of the skull. Nichols reports 11 cases in 32
autopsies (34 per cent.).


=Symptomatology.= As the direct result of the blow the patient is
‘concussed’, remaining in that condition for a variable period of time,
a matter of seconds, minutes, or hours, according to the nature of the
associated damage to the bone and brain. In the most typical cases, the
patient, on regaining consciousness, should recover--again for a
variable period of time--complete control over mind and body, returning
to work, walking home or visiting hospital or doctor. More usually,
however, he remains slightly dazed, though recognizing his surroundings
and capable of answering questions. In any case--unless the hæmorrhage
is accompanied by grave cerebral lesion--there should be some attempt at
recovery, some return to consciousness. The importance of this ‘lucid
interval’ cannot be over-estimated. It should be noted, however, that
this interval of consciousness is not of itself absolutely diagnostic of
middle meningeal hæmorrhage--it ought to be associated with definite
localizing symptoms of brain compression (see below). I have encountered
several cases in which this lucid interval was present, and in which
operative procedures were carried out in the anticipation of finding an
extra-dural extravasation, only to find a subdural hæmorrhage. Such
subdural hæmorrhages are not infrequently associated with a similar
return to the conscious state, but are rarely--if ever--accompanied by
the early development of symptoms of localized brain compression. In the
event of doubt as to whether the surgeon has to deal with an extra or
subdural extravasation lumbar puncture will probably clear up the
diagnosis.

The duration of this ‘lucid’ interval is exceedingly variable. It is
usually a matter of minutes or hours, though both König and Wiesman
narrate cases in which eight days elapsed before the onset of definite
localized compression symptoms. I also have recollections of a case in
which the patient walked some miles across the moor to see his doctor,
and finding him away from home, walked home again, then becoming
unconscious and dying shortly afterwards.

All depends on the calibre of the vessel injured and on the existence of
a safety-valve, by means of which some of the extravasated blood can
escape externally (see p. 97).

No rule can be laid down as to the duration of this ‘lucid’ interval,
but all authorities are agreed as to its existence, even though it may
be of exceeding short duration. Its importance, from a clinical point of
view, cannot be overestimated. It was present in 43 out of 63 cases
reported by Jacobson, well marked in 32 (50 per cent.), less marked in
11 (18 per cent.). It was observed in 60 per cent. of cases that came
under my care.

During this period the blood is occupied in stripping away the dura from
the bone--the larger the vessel the easier the task and the shorter the
‘lucid’ interval.

The further progress of the case may be considered according to the
_general and local effects_ of the hæmorrhage.


=General effects.= As soon as the clot becomes of sufficient size as to
exert general pressure on the brain, symptoms of compression become
evident, the patient first entering on the stage of ‘slow cerebration’.
He is dull and apathetic, showing marked delay in responding to
questions. As the pressure increases, he gradually passes into a state
of unconsciousness.

The pulse becomes full and slow, the blood-pressure rises progressively
(to 200 or more mms. of Hg.), respiration is laboured and stertorous,
and the temperature raised (rising progressively). The skin is hot, the
face turgid and cyanosed. If the pressure is unrelieved, stimulation of
the medullary centres gives place to exhaustion, the pulse becoming
irregular and rapid, blood-pressure falls rapidly, and respiration is of
irregular rhythm and finally Cheyne-Stokes in character. Finally, the
patient becomes completely comatose, the pupils are widely dilated, and
the cornea insensitive. Both urine and fæces may be passed (through
paralysis of the sphincters), the extremities exhibit flaccid paralysis
and the reflexes are abolished. Death occurs primarily through paralysis
of the respiratory centre.


=Local effects.= In many cases considerable help to diagnosis may be
obtained by external examination--bruising and ecchymosis, or definite
hæmatomata, in the temporal or parietal regions. In some cases the
hæmatoma may pulsate, and in others the application of pressure to the
hæmatoma will lead to the development of fits involving the face and
extremities on the contra-lateral side. Copious hæmorrhage from the ear
should always arouse suspicion as to the probability of an extra-dural
hæmorrhage (see p. 97).

The _anterior_ branch of the artery, as it passes upwards towards the
vertex, overlies the pre-Rolandic or motor area. The pressure exercised
on that region of the brain leads--according to the site of
extravasation and the degree of pressure exercised--to the development
of twitchings, convulsions, spasticity, or paralysis of the muscles of
the face, upper and lower extremities on the contra-lateral side of the
body.

[Illustration: FIG. 51. TO ILLUSTRATE COMPRESSION OF THE BRAIN. As
produced by an extra-dural hæmorrhage from the posterior branch of the
middle meningeal artery.]

The late Professor von Bergmann[26] pointed out that the arm area is
most commonly affected, and that the leg area is never alone implicated.
Wiesmann[27] states ‘that isolated paralysis of the leg area is never
seen, but only paresis when the arm is paralysed, or both may be
similarly affected at once; convulsions may precede the affection’.

In discussing the frequency of local compression effects, Wiesmann
points out that some abnormal condition of the opposite extremities was
only absent in 16 out of a total of 257 cases. In 37 cases reported by
Jacobson,[28] hemiplegia, of a greater or lesser extent, was present in
19 (50 per cent.). The same authority explains that ‘with regard to the
onset of convulsions, if there be restlessness, spasmodic twitchings, or
movements of the limbs, it is only too probable that in addition to
middle meningeal hæmorrhage, contusion or laceration of the
brain-substance will be found at more places than one’.

In cases that have come under my observation twitchings of the muscles
of the face and upper extremities were observed in 37 per cent. of
cases, and paralysis in the same number. Some alteration in the
condition of the muscles on the contra-lateral side was present
therefore in 74 per cent. of cases.

If the hæmorrhage be situated on the left side of the brain, both motor
and sensory cortical speech areas may be involved, especially the
former.

With respect to _reflexes_, it has previously been stated that the
reflexes are abolished. This is true with respect to the later stages of
fully-developed compression. In the earlier state the reflexes on the
contra-lateral side may be increased, the difference between the two
sides affording some help in the differential diagnosis.


=Pupillary changes= are variable. According to Jonathan Hutchinson, the
pupil on the affected side becomes dilated, the blood extending inwards
towards the cavernous sinus and exercising direct compression of the
third nerve. The frequency with which a dilated pupil occurs in cases of
middle meningeal hæmorrhage, and the causation thereof, are, however,
matters of dispute. Phelps writes as follows: ‘Reference to cases cited
show that the so-called Hutchinson pupil may be observed as well in
hæmorrhages occurring in other situations than the middle fossa, and in
some cases of cerebral lesion without injury at all. There is no reason
to doubt that it is the result of cerebral contusion, but in what
relation they stand to specific cerebral injuries is undetermined.’

Walton states that ‘doubtless various factors play an important part in
producing the dilated pupil, but if disorders of any simple mechanism
are to be credited with the production of the Hutchinson pupil or other
pupillary changes, the only lesion worthy of the place is disturbance,
irritative or paralytic, of the intracranial fibres of the cilio-spinal
tract’.

The late Professor von Bergmann, from 70 cases, reports as follows:--

  In 39 cases both pupils were markedly dilated (56 per cent.).

  In 7 cases both pupils were markedly contracted (10 per cent.).

  In 20 cases the pupil on the same side was dilated (30 per cent.).

  In 4 cases the pupil on the opposite side was dilated (6 per cent.).

Parsons, in answering some queries in 1903, writes:--

  ‘I should anticipate from cortical irritation bilateral pupillary
  dilatation, perhaps more marked on the opposite side: from pressure
  the opposite effects, so far as mere cortical paralysis goes, but this
  would be more liable to be vitiated by vascular changes--the complex
  condition seen in coma. It is very difficult to elicit pupillary
  constriction by cortical stimuli--very easy to elicit dilatation, but
  always bilateral though often more marked on the opposite side.’

In cases examined by me the following conditions were found:--

  Pupils equal                                 46 per cent. of cases
  Pupils constricted on the affected side      36 per cent. of cases
  Pupils dilated on the affected side          18 per cent. of cases

From my experience, therefore, and from that of the authorities quoted
above, it would appear that alterations in the size of the pupil are of
very doubtful significance in the diagnosis of middle meningeal
hæmorrhage, and that the ‘Hutchinson pupil’ is but rarely observed.

The results obtained by ophthalmoscopic examination are of much greater
value. Such investigations should be carried out as a routine procedure.
In the earlier stages of the hæmorrhage some œdema of the disk, together
with dilatation of retinal veins and diminution in the calibre of the
arteries, will be observed on the affected side. This affords a most
valuable aid in the differential diagnosis as to the side on which the
hæmorrhage is situated--not always such a simple matter as appears at
first sight.


=Treatment.= Operation is indicated in all cases of middle meningeal
hæmorrhage if the condition of the patient be compatible with such
treatment. The earlier the operation is carried out the better.


=Operation.= _For Hæmorrhage from the anterior branch._ After the usual
preparatory treatment, the ‘site of election’ for trephining is marked
out on the scalp by taking a point which lies 2 inches posterior to the
external angular frontal process, and the same distance above the
zygoma. A bradawl may be introduced so as to indent the external table
of the skull, thus aiding the subsequent accurate application of the
trephine.

[Illustration: FIG. 52A. EXPOSURE OF THE BRANCHES OF THE MIDDLE
MENINGEAL ARTERY. _First stage._ Suitable scalp-flaps have been turned
down, and the skull has been trephined over the ‘sites of election’ for
exposure of both anterior and posterior branches.]

[Illustration: FIG. 52B. EXPOSURE OF THE BRANCHES OF THE MIDDLE
MENINGEAL ARTERY. _Second stage._ The trephine-holes have been enlarged
with the craniectomy forceps in the required directions.]

The incision commences immediately posterior to the external angular
frontal process, curves upwards and backwards along the temporal crest,
and terminates in front of the tragus of the ear. The flap, comprising
skin, temporal fascia and muscle, and pericranium, is turned to its
zygomatic base and all bleeding-points secured.

The subsequent procedures vary according to the condition of the bone:--

_If there be no fracture of the bone_, the pin of the trephine is
applied to the indented spot and the disk of bone removed. After the
removal of the disk the clot will be exposed; but, in order to obtain
full exposure, the gap must be enlarged with the craniectomy forceps,
mainly in the upward and downward directions.

_If a fissured fracture be found_, the trephine is applied in close
relation to the intersection of the line of the artery and the line of
the fracture, the gap being enlarged in the required direction.

_When the fracture is comminuted_, the fragments of bone are either
elevated or removed until sufficient room has been obtained.

The greater part of the clot can be removed with a Volkmann spoon, or
with an ordinary teaspoon, and the region flushed out with hot saline
solution.

_To secure the bleeding-points._ When the artery is injured beyond the
limits of the gap, the bone must be nibbled away till the bleeding-point
is exposed. In some cases it may be necessary to remove a considerable
portion of the bone entering into the formation of the temporal fossa.
In the meantime, hæmorrhage may be controlled by plugging towards the
base of the skull with strips of gauze. Sufficient room having been
obtained, the gauze is withdrawn, when smart sponging should enable the
operator to determine the source of the hæmorrhage. At this stage of the
operation, a head-lamp is useful. After the exposure of the
bleeding-points, the following measures can be adopted whereby to arrest
the bleeding:--

(_a_) The application of a ligature or of silver ‘clips’ (see Fig. 6) on
either side of the bleeding-point.

(_b_) The vessel may be underrun on either side of the bleeding-point.

(_c_) The vessel may be seized with artery forceps and twisted.

(_d_) The hæmorrhage may be arrested by means of gauze plugs.

(_e_) The foramen spinosum may be occluded with bone or wooden pegs.

(_f_) The common or external carotid arteries may be ligatured.

Every effort should be made to control the hæmorrhage by means of
ligature, silver clip, underrunning, or torsion. Gauze plugs may usually
be relied on to stop the bleeding, but they possess the great
disadvantage of exercising pressure on the cortex and preventing
expansion of the brain.

Occlusion of the foramen spinosum and ligature of the carotid arteries
complicate and prolong the operation. The foramen spinosum is occluded
in the following manner: the dura mater is quickly stripped up with the
fingers away from the base of the skull, the soft parts gently but
firmly retracted and the foramen identified. Its occlusion may be
effected by means of a sterilized wooden match or bone peg, by a small
piece of bone derived from those osseous fragments which have been
removed during the operation, or with the aid of a piece of catgut; in
each case the occluding medium should be well driven into the foramen.

It is open to doubt whether ligature of the carotid arteries is ever
necessary, though several cases have been recorded in which such a
procedure was carried out. The external carotid should be tied in
preference to the common vessel, further interference with the
blood-supply of the brain increasing necessarily the risk of cerebral
œdema, &c.

The hæmorrhage having been arrested by one or other of these methods,
the cavity is thoroughly washed out with hot saline solution and
drained, a small rubber drainage-tube being brought out through the
scalp-flap. The tube should be removed after twenty-four to thirty-six
hours, according to the circumstances of the case.

_For hæmorrhage from the posterior branch._ The ‘site of election’ for
exposure of the posterior branch lies at the intersection of the two
following lines:--

A line drawn backwards from the upper border of the orbit parallel to
Reid’s base-line.

A line drawn vertically upwards from the posterior border of the mastoid
process.

The trephine is applied, the disk removed, and the gap enlarged with the
craniectomy forceps in the forward and backward directions. The hæmatoma
is evacuated and the bleeding arrested after the methods enumerated
above.


=Results.= The ultimate result of operation for middle meningeal
hæmorrhage depends on two factors--the time at which operation is
carried out, and the question of brain lesion. There is every reason to
believe that, when treated early and when uncomplicated by brain injury,
the prognosis, both immediate and remote, is wholly satisfactory.

Wiesman[29] collected 257 cases, of which 110 were submitted to
operation, with a mortality of 27 per cent. Of the cases in which no
operation was performed 88 per cent. died.

Duchaine[30] reports 27 cases in which operation was carried out, with
death in 6 cases only, a mortality of 22 per cent.

Von Bergmann collected 110 cases treated by operation, with 74
recoveries and 36 deaths, a mortality of 32·27 per cent.

Blake only lost 3 cases out of a total of 42 submitted to operation.

Even when every allowance is made for the fact that operative measures
were adopted in the more hopeful cases, the above statistics show
conclusively that early operation affords great hope of cure.

[Illustration: FIG. 53. A BASIC FRACTURE WITH LACERATION OF BOTH CAROTID
ARTERIES.]

Before passing on to =subdural hæmorrhage=, it will be convenient to
discuss briefly the question of injury to the =internal carotid artery=.

This vessel, during its forward passage in the outer wall of the
cavernous sinus, from the posterior to the anterior clinoid processes,
crosses the line of the typical middle fossa fracture (see p. 84). The
artery is loosely embedded in the sinus, it is protected by the third,
fourth, ophthalmic division of the fifth and sixth nerves, and it is
situated some distance above the level of the base of the skull. In
spite of this degree of protection from injury, the artery may be
lacerated in this part of its intracranial passage. The basic fracture
is necessarily of a very severe nature. Two cases have come under my own
care: one in which both arteries were torn across, the fracture passing
from one middle fossa to the other, with such wide separation of the
anterior and posterior segments of the skull that the two were freely
movable on one another (Fig. 53), whilst in the second case, the
fracture, originating in the left frontal region, passed backwards
across the anterior fossa, comminuting the base in the region of the
cavernous sinus, lacerating that sinus and tearing the artery (Fig. 54).

[Illustration: FIG. 54. A BASIC FRACTURE WITH LACERATION OF THE
CAVERNOUS SINUS. A, The optic nerve; B, The cavernous sinus; C, The
third nerve; D, The internal carotid artery.]

In both cases death was almost instantaneous, blood pouring from the
nose and mouth.

In some few cases the vascular lesion is confined to a minute tear in
the coats of the vessel, a fistulous communication being formed between
the artery and the cavernous sinus--arterio-venous aneurysm. This
condition is discussed on p. 204.


II. Subdural hæmorrhage.

Hæmorrhage into the subdural space may be (_a_) diffuse, or (_b_)
localized.


(_A_) =Diffuse subdural hæmorrhage.= The blood may be derived from one
of the great sinuses of the brain or from superficial cerebral vessels
(laceration of the brain).

The _superior longitudinal sinus_ may be torn by the in-driving of
fragments of bone in a comminuted depressed fracture of the vertex, or
by wide separation along the line of the sagittal suture. Blood is
diffused throughout the subdural space, on one or on both sides of the
falx cerebri, but always tending to gravitate towards the lower limits
of the supra-tentorial space.

In the event of the wound being compound, air may enter into the sinus.
Insomuch, however, as the sinus pressure is, under normal conditions,
positive, this complication is of rare occurrence, unless the patient is
in a state of profound shock, from loss of blood, or suffers from urgent
dyspnœa.

Allusion should also be made to the condition described by Stromeyer, as
‘sinus pericranii’, where a subpericranial hæmatoma communicates with a
venous sinus. Such hæmatomata may pulsate, are more or less reducible on
pressure, and are increased on straining or on the application of
pressure to the internal jugular vein.

The _lateral sinus_ may be laid open in any part of its course, more
especially at the angle of junction between the lateral and sigmoid
sinuses, in close relation to the occipito-mastoid suture, a region not
infrequently involved in basic fractures. The blood effused will occupy
the supra- or infra-tentorial spaces according to the situation of the
rent in the sinus-wall.

The _cavernous sinus_ is frequently involved in anterior and middle
fossa fractures. The blood effused usually escapes into the nose and
mouth.

[Illustration: FIG. 55. A COMMINUTED FRACTURE OF VAULT AND BASE, THE
BASIC FRACTURE INVOLVING BOTH MIDDLE AND POSTERIOR FOSSÆ. The middle
fossa fracture, on the left side, follows the usual course. The
posterior fossa fracture resulted in laceration of both lateral
sinuses--at the usual site, junction of sigmoid and lateral sinuses.
Probes are inserted at each site of laceration. The resultant hæmorrhage
was mainly intradural, but, as is seen in this figure, the dura mater of
the posterior fossa is stripped away from the bone by an extra-dural
extravasation.]


=Symptoms.= The rapid diffusion of blood throughout the subdural space,
and the usual coexistence of extensive injury to bone and brain, seldom
permit of the development of such definite symptoms as might accurately
define the localization of the hæmorrhage. The most important feature in
the diagnosis lies in the fact that compression symptoms are early in
onset and progressive in nature. The ‘lucid’ interval, so prominent a
feature in middle meningeal extravasations, is either absent or of such
short duration as to be difficult of recognition. The rapid development
of symptoms pointing to brain compression, and the nature of the injury
itself should enable the surgeon, in the majority of cases, to come to
the conclusion that the patient is suffering from diffuse subdural
hæmorrhage. In all cases of doubt, lumbar puncture should be carried
out, the presence of blood-corpuscles in the cerebro-spinal fluid
confirming the diagnosis.


=Indications for operation.= Whether one considers the case from the
point of view of the more immediate prognosis or from the more remote
aspect of the case, operation is indicated, if the condition of the
patient is compatible with such treatment. In considering the
advisability of adopting an active form of treatment, it must be taken
into account that, if the patient recovers without operation, the
presence of an extensive subdural blood-clot must necessarily interfere,
as an after-result, with the functions of the cortex, and that the
removal thereof affords considerable hope of permanent cure.


=Operation.= Operative measures may be considered as follows:--

The treatment of the fracture and of the dural rent.

The treatment of the subdural extravasation.

_The treatment of the fracture and of the dural rent._ A scalp-flap is
framed, suited to the occasion and formed with due regard to existent
scalp laceration. The fracture being fully exposed, depressed or
comminuted fragments of bone are elevated or removed. Complete exposure
of the sinus-wall, both in front and behind the site of laceration, is
required, and for this purpose the craniectomy forceps may be called
into requisition. In the event of copious bleeding during these
procedures, strips of gauze should be inserted on either side of the
sinus rent between the dura and the bone, thus compressing the sinus and
stopping the bleeding.

The sinus rent may be treated after one or other of the following
methods:--

1. It may be sewn up with mattress sutures of fine catgut, by which
means it may be possible to stop the hæmorrhage without interfering with
the sinus blood-stream.

2. The open mouth of the sinus may be puckered up by means of a
purse-string suture.

3. The needle may be passed right round the sinus on either side of the
rent, piercing the falx cerebri in the case of the superior
longitudinal sinus and the tentorium cerebelli in wounds of the lateral
sinus. The two ligatures are then tightened up and the bleeding
controlled.

4. The gauze plugs (see above) may be allowed to remain for twenty-four
hours or more, and then carefully withdrawn.

_The treatment of the subdural hæmorrhage._ Though the complete
evacuation of the clot is seldom practicable, much may be done to remedy
the condition. The tenseness of the dura mater, the absence of
pulsation, and the peculiar plum-colour imparted to that membrane by the
presence of underlying blood-clot point to the nature of the trouble.

The dura mater is incised and the presenting clot removed, as far as
circumstances permit, with the aid of a spoon and irrigation (hot saline
solution at a temperature between 110° and 115° Fahrenheit). Free
drainage must be supplied, and it is necessary, therefore, that a
counter incision should be made at the most dependent part of the clot.
A suitable region may present itself if the bone be extensively
comminuted. Under other circumstances, a narrow channel may be cut in
the bone, prolonged in the downward direction, till the lower limits of
the clot have been reached (see Fig. 56).

[Illustration: FIG. 56A. THE OPERATIVE TREATMENT OF SUBDURAL HÆMORRHAGE.
_First stage._ The skull has been trephined over the upper part of the
clot and the bone cut away in the downward direction in order to reach
the lower limits thereof. The dura mater has been incised, crucially in
the upper part and vertically in the lower part.]

[Illustration: FIG. 56B. THE OPERATIVE TREATMENT OF SUBDURAL HÆMORRHAGE.
_Second stage._ The clot has been removed and the dura mater sewn up. A
drainage tube has been inserted so as to drain the subdural region
through the lower part of the scalp-flap.]

A rubber drainage-tube may be inserted in the manner depicted in the
same figure. Except at the point of emergence of the tube, the dura
mater is sewn up (with fine interrupted catgut sutures).


(_B_) =Localized subdural hæmorrhage (subdural hæmatocele).= We are
greatly indebted to Bowen[31] for our knowledge of subdural hæmatomata.
That subdural hæmorrhage might take the form of a localized collection
was a recognized fact, but the condition was but little understood, the
typical clinical symptoms were not recognized, and surgeons hesitated to
adopt surgical remedies. All these facts impeded advance in both
diagnosis and treatment. Subdural hæmatoceles, even at this date, are
often regarded as rarities, but, in the light of present knowledge, it
would appear that wider recognition of the hæmorrhage in its clinical
aspect will show that such ideas are erroneous.

In the preceding section it was shown that subdural extravasation
resulting from sinus-injury tends to become diffused throughout the
subdural space. With respect to localized hæmorrhages our data are by no
means complete, but all available evidence tends to show that subdural
hæmatoceles are dependent on laceration of the pia-arachnoid vessels--a
condition practically synonymous with superficial laceration and
contusion of the cortex. The blood, derived from small cerebral veins
and minute cerebral arteries, exercises primarily but slight pressure
effect. Its force is expended on compressing and emptying the subjacent
and surrounding cerebral vessels, producing, in other words, a condition
of _local cerebral anæmia_. This pressure is insufficient to lead to the
development of general compression, but suffices to produce certain
rather indefinite symptoms. We have, therefore, before us a very
different picture to that depicted in cases of middle meningeal
hæmorrhage. In such extra-dural hæmorrhages some definite period of time
must elapse before the dura mater is sufficiently stripped from the bone
to allow of the formation of a clot of size sufficing to exercise both
local and general compression effects. Pressure effects then become very
manifest.

On the other hand, in localized subdural extravasations there is an
immediate effect, for the brain is contused or lacerated. On recovering
from the immediate effects of the injury--concussion of a greater or
lesser degree of intensity--the patient does not regain complete mental
and bodily convalescence. He suffers from symptoms suggestive of brain
irritation--headaches, photophobia, mental irritability, insomnia, loss
of appetite, the pulse accelerated, and the temperature slightly raised.
Later on, more definite symptoms arise, but, intervening between the day
of the accident and the time at which these more definite localizing
symptoms develop, there is an unmistakable _latent_ period--a period to
be sharply differentiated from the previously mentioned _lucid_ interval
(see p. 139).

This ‘latent’ period lasts for a variable period of time--seldom less
than a week or more than three months. At the end of that time the
picture changes, and the patient evidences symptoms obviously referable
to local brain compression. From a clinical point of view it is
fortunate that subdural hæmatoceles tend to involve the fronto-parietal
region with the consequent development of motor symptoms, especially
paresis or paralysis of the contra-lateral side. Hence the name
sometimes applied to the condition--traumatic late apoplexy. The speech
areas are implicated if the injury be situated on the left side.
Paralysis limited to the lower extremity is exceedingly suggestive, such
a palsy occurring only with the greatest rarity in extra-dural
hæmorrhages (from the middle meningeal artery).

If the pressure be unrelieved by operation the patient passes from the
excitatory to the paralytic stage of brain compression, gradually
falling into a condition of coma, the pulse increasing in frequency and
the respiration becoming more and more embarrassed.

In the study of this condition, the following are the points to which
special attention should be paid:--

1. The comparative want of severity with respect to the injury received.

2. The absence of any ‘lucid’ interval, such as is present, for example,
in middle meningeal hæmorrhage.

3. The presence of a definite ‘latent’ period.

4. The late development of symptoms pointing to general and local brain
compression.

Finally, it may be stated in general that the more indefinite and the
more deferred the pressure symptoms, the greater the probability that we
have to deal with a localized subdural hæmorrhage. Lumbar puncture may
materially aid in the differential diagnosis between extra-dural and
subdural hæmorrhages.

The following case affords a typical example of subdural hæmatocele:--

  An elderly man fell down, striking the right side of the head against
  the pavement. He lost his senses for a few minutes and was then
  brought to the hospital, dazed and complaining of headache (note the
  absence of any _lucid_ interval). He was sent home in a cab and was
  assisted to bed by his wife. He kept to his bed during the next week,
  complaining of constant headache, and was exceedingly irritable (this
  is the ‘latent’ period). Towards the end of the third week his wife
  noticed that he seldom used the left upper and lower extremities. This
  paresis increased steadily, the face was drawn to the right side, and
  his condition became so serious that the wife brought him again to the
  hospital (this is the ‘manifest’ period).

  When seen by me he was only partly conscious, the mental condition
  varying, however, during the day. He was exceedingly irritable,
  muttering to himself in a low tone, words being more or less
  unintelligible. The left upper extremity was paralysed, the face drawn
  to the right side, and the left lower extremity was but little used.
  The pupils were equal, the disks normal. The temperature in the left
  axilla was two degrees lower than on the opposite side.

  The hæmatocele was exposed, cleared out, and the cavity drained.
  Recovery was rapid and complete. Two years later all was well.


=Operation.= The lesion is usually of so gross a nature that little
difficulty will be experienced in determining the site for trephining.
The protective gauze and scalp-tourniquet are applied as usual (see p.
14), and a bradawl introduced through the scalp so as to indent the
external table and allow of the subsequent accurate application of the
trephine. A scalp-flap, suited to the occasion, is framed, the skull
trephined, and the disk of bone elevated and removed. The appearance of
the dura mater now allows the operator to verify his diagnosis--the
membrane is non-pulsatile, it bulges markedly outwards and presents a
blue-purple colour. The bone is then nibbled away in the downward
direction towards the lower limit of the clot, the scalp incision being
prolonged according to requirements.

In the region of the trephine-hole the dura is incised in a crucial
manner, and the four flaps held aside by catgut sutures passed through
the apex of each flap. A blunt director is introduced beneath the dura,
passing towards the lower limit of the clot, and the membrane slit up to
within a short distance of the lower margin of the gap. All meningeal
vessels that cross the line proposed for dural section must first be
underrun on either side of that line. Retraction of the dura will now
allow of adequate exposure of the underlying hæmatoma. Its removal can
be carried out with the aid of a spoon, and by means of gentle
irrigation (hot saline at a temperature between 110° and 115°
Fahrenheit). It is usually impossible to remove the whole of the
coagulum, but the greater portion can be got rid of in the manner
described.

The dura mater is approximated above by the cross-union of the four
apical sutures, whilst the downward prolongation is also sutured except
at the most dependent point, where a rubber drainage-tube is inserted
beneath the dura mater and brought out through the scalp-flap (see Fig.
56). This tube should be anchored to the dura mater with a single fine
catgut suture.

The tube should be allowed to remain in position for at least thirty-six
hours. In this the surgeon must be guided by the amount of discharge and
the general progress of the case.


=Results.= The most complete results obtained by operative treatment are
supplied by Bowen, who classifies a series of 72 cases as follows:--

Class A. Subdural hæmorrhage, apparently without other serious injury to
bone or brain.

  36 cases. 22 recovered after operation.
            14 died--11 without and 3 after operation.

Class B. With serious brain-injury.

  36 cases.  6 recovered after operation.
            30 died--10 without and 20 after operation.

In other words, every case died in which no operative measures were
adopted, whilst after operation 28 recovered and 23 died. My own
experience is limited to 4 cases, 3 of which recovered.


=Pia-arachnoid hæmorrhage.= From evidence obtained at post-mortem
examinations, it may be concluded that the great majority of cases of
severe head-injury--especially those in which ‘irritation’ of the brain
is a prominent feature--are associated with pia-arachnoid hæmorrhage.
This is evidenced by the presence of a film of blood and serum over
certain regions of the brain, not confined to the region subjacent to
the skull area primarily involved, but also present over the opposite
pole of the brain (injury by contre-coup).

Subpial hæmorrhage differs from the subarachnoid variety in that the
blood follows the invaginations of the pia mater, lining, therefore,
both major and minor cerebral sulci. Subpial and subarachnoid
hæmorrhages are, however, generally co-existent, and the
term--pia-arachnoid hæmorrhage--aptly describes the conditions commonly
found.

The =symptoms= resulting from such blood extravasations are such as are
described in the sections dealing with concussion and irritation of the
brain (see p. 166).


INJURY TO THE BRAIN

Injury to the brain must always be regarded as by far the most important
of the many complications associated with fracture of the skull. A
fracture is not necessarily accompanied by brain-injury, and laceration
of the brain may exist without a fracture. There can, however, be no
question that the more severe cases of head-injury are almost invariably
associated with some degree of brain-injury--varying from contusion to
extensive laceration, cortical or central.

No part of the brain is exempt from injury, but two regions, the
antero-inferior aspect of the frontal lobe and the antero-external
aspect of the temporo-sphenoidal lobe, show a special liability to
contusion and laceration.

The brain may be injured immediately subjacent to the site at which the
blow is delivered (direct injury), or at the pole directly opposite that
at which the blow was applied (indirect injury).

Direct injury results from the in-driving of comminuted and depressed
fragments of bone, from the passage of a foreign body, and from the
direct transmission and diffusion of forces through the subjacent
cerebral substance.

The indirect forms of injury are less readily explained. Their frequency
cannot be disputed. I drew attention to the subject in my Hunterian
Lectures in 1904, there stating that indirect injury to the brain was
more common than the direct form. My opinion is confirmed by Phelps,[32]
who states that injury by indirect violence is of almost constant
occurrence.

Three theories have been advanced in explanation:--

1. ‘Their production has been ascribed to the change in form that is
suffered by a skull in virtue of its elasticity when subjected to
violence which causes distortion of the brain to the point of bursting.’

2. ‘In the displacement of the cerebro-spinal fluid by the consecutive
depression and bulging that is believed to follow a blow on the head; a
momentary vacuum is formed at either axis of force, and the vessels of
the brain and meninges rupture from lack of support.’

Neither of these theories are tenable, insomuch as they are based on an
acceptance of the ‘bursting and compression’ theories (see p.
74)--theories which, in my opinion, it is impossible to accept.

3. The ‘contre-coup’ theory. According to this theory the injury is due
to sudden and violent displacement of the brain against the opposing
osseous barrier. This theory has been opposed by many--notably by
Helferich--on the ground that the brain is said to completely fill the
cranial cavity, and that ‘shaking’ from side to side is impossible.

This theory affords, however, the most satisfactory explanation of
contralateral laceration. The following points may be advanced in its
favour:--

(_a_) The frontal and temporo-sphenoidal lobes are more liable to
contusion and laceration than any other parts of the brain, both regions
possessing certain anatomical relations accounting for their ready
injury. The frontal pole is related to the angle of junction between
the horizontal and vertical plates of the frontal bone, the
temporo-sphenoidal lobe to the cul-de-sac, at the anterior part of the
middle fossa, that is overhung by the wings of the sphenoid bone.

(_b_) The lacerated area is almost invariably situated at that part of
the brain which lies opposite to the region struck in the line of the
transmitted force. Furthermore, brain lesions are most prevalent when
the accident results from a fall from a height, a class of accident in
which ‘shaking’ of the brain is most likely to occur, and least common
when the basal fracture is dependent on a bilateral compression force.

(_c_) The statements that ‘shaking’ cannot take place, and that the soft
cerebral substance cannot be driven forcibly and violently against the
opposing bony barrier, so as to be locally bruised and torn, are
incorrect.

That such violent displacement of the brain can and does occur is proved
by the following case:--

  A prize-fighter was knocked out by a blow on the right side of the
  head, dying a few hours later. The post-mortem revealed no fracture of
  vault or base, but a linear laceration of the brain on the mesial
  aspect of the right hemisphere which exactly corresponded to the free
  margin of the falx cerebri. In this case, therefore, conclusive
  evidence was obtained that the brain had been driven from right to
  left against a firm and resisting barrier, corresponding laceration
  resulting.

The lacerated area is usually cone-shaped, the base corresponding to the
surface of the brain, the apex facing towards the lateral ventricles. In
the most severe cases the anterior or lateral horns of the lateral
ventricles may be involved at the apex of the cone, and, in the event of
further cerebral softening, the horns of the ventricles may, as it were,
bulge outwards, thus assisting in the formation of those traumatic
cephaloceles that communicate between the lateral ventricle and the
surface of the brain.

On the other hand, if the degree of laceration be slight and the injury
compatible with life, organization and partial resolution takes place,
with the formation, in nearly all cases, of adhesions between the cortex
and the membranes, of false membranes, arachnoid cysts, and of blood
cysts. In the more serious cases cerebral fibrosis results, in direct
proportion to the degree of cerebral destruction, with corresponding
degeneration, both of the cerebral cortex and of the tracts that evolve
therefrom.


=Symptoms.= Certain regions of the brain may, when injured, give rise to
localizing symptoms. More generally, however, all localizing features
are obscured by an overpowering element--the presence of concussion,
irritation, or compression of the brain.

Still, in some cases, the localizing features are sufficiently marked,
at some period of the case, to allow of a more definite diagnosis. The
symptoms, therefore, must be considered under the two heads, (A)
_localizing_, and (B) _general_.


A. Localizing symptoms.


_Localizing to the frontal lobes._ Phelps,[33] from a series of 130
cases, arrived at the following conclusions--that, ‘in nearly every case
in which consciousness was retained or regained, and the mental
faculties not perverted by general delirium, laceration of the left
frontal lobe was attended by default in intellectual control, and that
the lesion was usually of the anterior region and implicated its
inferior surface.’ ‘Subcortical disintegration was characterized by
abrogation of mental power, and superficial laceration by aberration in
its manifestations.’ And secondly, that, ‘in nearly every instance in
which laceration was confined to the right side, the mental faculties
remained unaffected, except as they were obscured by delirium and stupor
occasioned by coincident general lesion.’

Although the above statements have not altogether been confirmed by
cases that have come under my observation, yet, coming from such a
source, they must be accepted unless refuted.

Bianchi states that, after extirpation of the frontal lobe of the ape,
the whole intellectual life of the animal is changed. Perception,
attention, inhibition, and in particular memory and association are
enfeebled. The psychical tone is lowered; the ape lacks initiative,
courage, and spirit.

Laceration of the under aspect of the lobe may, by direct involvement of
the olfactory region, interfere with the faculties of smell and taste.


_Localizing to those parts that minister to the function of speech._ The
condition of the patient usually prevents one from obtaining early
information as to the power of speech. Isolated lesions of the posterior
part of the third left frontal convolution result in _motor aphasia_, a
condition characterized by the inability on the part of the patient to
speak, in spite of the fact that comprehension is unimpaired. The
brain-injury is, however, seldom so defined as to be characterized by
loss of speech without other phenomena. In very close relation to the
area responsible for speech is the _writing_ centre, situated at the
posterior end of the middle frontal gyrus, near the centre for the
movements of the hands and fingers. Injury to this centre results in
_agraphia_ and _alexia_.

_Word-deafness_ results from lesions implicating the upper
temporo-sphenoidal lobe, and _word-blindness_ from injuries to the
supramarginal and angular gyri (see Fig. 57).

[Illustration: FIG. 57. THE AREAS CONCERNED IN SPEECH EXPRESSION.]

Phelps pointed out that the lesion must be an extensive one if the
symptoms included under the term _sensory aphasia_ (word-blindness,
word-deafness) are to be evolved. No localized injury to any small area
suffices, and the cortex must be deeply involved. Lacerations of the
brain are usually of so gross a nature that further differentiation is
seldom to be obtained. Here it might be noted that the cortical centres
responsible for speech and its accessories, word-seeing, word-writing,
and possibly word-hearing, are all situated on the left side in normal
right-handed individuals. The corresponding areas on the right side may
be regarded as ‘silent’ areas, and may be utilized, if desired, for
decompression purposes. No operation, with that purpose in view, should
be carried out, however, unless the surgeon is assured that the patient
is right-handed in his actions. A case has recently come to my
knowledge where a right-parietal decompression operation was carried out
with disastrous results.


_Localizing to the temporo-sphenoidal lobe._ The relation of sensory
aphasia to lesions of the temporo-sphenoidal lobe has already been
mentioned. The anterior poles of this portion of the brain, a region
frequently involved in head injuries, may lead to the development of
impaired smell and taste, especially if the lesion includes the uncinate
lobe and be situated on the left side. In other respects, the
temporo-sphenoidal lobe may be regarded as a ‘silent’ area of the brain.


_Localizing to the pre- and post-central convolutions._ Injury to the
pre-central or motor area usually leads to the development of definite
symptoms--twitchings, convulsions, or paralysis of the face and
extremities on the contra-lateral side. In the earlier stages reflexes
are abolished. Later on, as the result of degenerative changes in the
pyramidal tracts, spasticity, contractures, and rigidity, with increased
reflexes will be observed in the affected limbs. On the other hand, the
muscles do not show any reaction of degeneration. Babinski’s sign is
generally present.

Injury to the post-central convolutions might be expected to lead to
various alterations in tactile and muscle sense, in stereognosis, and in
sense of pain and temperature, but the general condition of the patient
seldom permits accurate demonstration. Such sensory disturbances are
more frequently observed as late results of head-injury.


_Localizing of the occipital lobes._ Laceration of the occipital lobes
may lead to homonymous hemianopia, for which defect it is probable that
the degree of laceration must be considerable, involving mainly the
mesial aspect of the occipital lobe (see Fig. 69). Schäfer has shown
that the greater portion of the occipital lobe may be removed in monkeys
without producing loss of vision, and it is only when the lesion
involves the parieto-occipital fissure and passes into the
occipito-temporal convolutions that loss of vision is permanent.

Slighter degrees of occipital injury may lead to subjective symptoms,
such as flashes of light, colour changes, &c.


_Localizing to the cerebellum._ Lesions of the cerebellum rarely permit
of the development of such localizing symptoms as are observed in
cerebellar tumours. Inco-ordination of movement, ataxia, and other
symptoms observed in cerebellar tumour formation are, from the general
condition of the patient, incapable of demonstration in cerebellar
laceration. It is necessary, however, to draw attention to the
significance of yawning and gaping. This symptom has been observed in
several recent cases, and, as far as my observation goes, is only
present in cerebellar lesions.

[Illustration: FIG. 58. THE CORTICAL MOTOR AND SENSORY AREAS.]

In the consideration of these localizing symptoms, it must be borne in
mind that brain lacerations are of an exceedingly gross nature, and that
there may be--as the late Professor von Bergmann[34] pointed
out--‘notwithstanding the severest brain symptoms, not the slightest
discoverable anatomical alteration in the brain. On the other hand,
notwithstanding the absence of all brain symptoms, extensive and
striking destruction of the brain substance.’


B. General symptoms.


Concussion or cerebral shock.

_Its pathology._ Concussion used to be regarded as implying a ‘molecular
disturbance’ of the brain--a definition so unsatisfactory that it may be
relegated to a desired obscurity. At the present day, though some
difference of opinion exists as to whether the condition is or is not
necessarily dependent in its development on associated cortical or
subcortical lesions, macroscopical or microscopical, concussion is
regarded as implying a condition of _acute cerebral anæmia_ through
sudden inhibition or paralysis of the vaso-motor centre.

With respect to the existence of visible lesions of the brain, Kocher
maintains that such lesions--hæmorrhages and the like--are necessarily
present, proposing that the term ‘brain concussion’ should be eliminated
in favour of ‘brain contusion’. On the other hand, the late Professor
von Bergmann pointed out that such a course was not possible, instancing
the many cases of concussion where contusion could not possibly have
existed.

There cannot, in my opinion, be any question as to which is the correct
view. It is unreasonable to ask one to believe that the milder cases of
concussion, cases in which the patient merely suffers from loss of
consciousness for a few minutes, from which he rapidly recovers and is
discharged from treatment within a few days, and from which he suffers
in the future from no remote ill effects whatsoever, it is unreasonable
to ask one to believe that such cases have experienced so severe a
lesion as brain contusion or laceration. Both these conditions would
require a long period of convalescence, and would tend to leave in their
train very serious after-results.

It is obvious, therefore, that there exists a degree of concussion from
which the patient can quickly and entirely recover. It is also clear
that in many cases the patient passes through a long and serious
illness, whilst, in some cases, a fatal termination may ensue--and that
too within a few hours. It is consequently clear that we have to deal
with varying grades of concussion, some of which are of so mild a nature
as to be clearly unassociated with definite cerebral lesion, whilst
others are of so serious a nature that death may take place within a
few hours, and in such cases the gravest cerebral lesions may be found
at the autopsy.

In other words, it would appear that concussion is more or less
dependent in its severity on the degree of associated cerebral change.

It is, however, to the milder type of case that we should turn in order
to determine what is exactly meant by concussion. In such cases the
patient merely suffers from a mild degree of _cerebral shock_, a
condition closely resembling shock in general. ‘Shock’ is defined as a
‘condition resulting from fall in blood-pressure, due to inhibition or
paralysis of the vaso-motor centre’. The afferent impulses that pass up
the various sensory paths inhibit or paralyse the vaso-motor centre, a
centre that has for its main function a tonic constricting influence on
the peripheral arteries. Hence, these vessels dilate atonically, the
blood collects in the great splanchnic area, and, insomuch as the
cerebral arteries possess no separate vaso-motor apparatus, they
passively follow the changes in the general circulation. The brain is
consequently in a state of arterial anæmia, the arteries relatively
emptied, the veins passively engorged.

Clinically, concussion or cerebral shock differs from ordinary shock in
one manifestation only--sudden loss of consciousness. This development
is readily explained on the ground that concussion results from a
violent blow applied in the near neighbourhood of the vaso-motor centre,
with consequent _sudden_ vaso-motor depression and _acute_ anæmia of the
cerebral cortex. This leads to immediate great fall of blood-pressure,
loss of consciousness, and lack of muscular control.

Statements have recently been brought forward to the effect that
concussion is in reality a mild type of compression. This view received
at first sight some confirmation from the experiments of Koch and
Filehne, who, from the application of consecutive slight blows to the
heads of dogs, showed that each blow resulted in bulbar stimulation
followed by bulbar depression. The blows being continued, the degree of
stimulation decreased and that of depression increased until exhaustion
and death resulted. During the periods of stimulation the pulse-rate
slowed, during those of depression it increased.

It should be noted, however, that concussion, as observed in the human
being, results from one sudden and violent blow. It may, I think,
safely be assumed that, in such cases, the stimulating effect of the
blow is entirely abolished in favour of an acute depression. And, as
Archibald[35] says, ‘their records of respiration, pulse, and
blood-pressure resemble far more closely the course of an increasing
compression, with its gradual slowing of pulse and respiration and
steady rise of blood-pressure, than that of concussion with its sudden
standstill of pulse and respiration and fall of blood-pressure.’

In _favourable cases_ the injury being of a comparatively mild nature,
the vaso-motor centre soon recovers tone, and, as the result of previous
depression, the vascular conditions are now reversed--_the stage of
depression_ giving place to the _stage of reaction_. The blood-pressure
rises, the carotids pulsate forcibly, the face is turgid and flushed,
the skin hot and moist, whilst the temperature rises, and the general
cerebral hyperæmia is evidenced by headache, restlessness, and perhaps
by delirium.

In the _more severe cases_ the vaso-motor depression is unduly
prolonged, or persists till death, the patient remaining concussed for a
considerable period of time, or dying in that condition. In these fatal
cases the post-mortem examination _usually_ reveals brain laceration,
but _always_ evidences considerable engorgement of superficial cerebral
veins, increase of cerebro-spinal fluid and œdema, both of the
pia-arachnoid region and of the brain substance itself. These latter
phenomena are accounted for by the fact that, insomuch as the venous
pressure and cerebro-spinal tension are equal, the greater the
engorgement of the cerebral veins the more extensive is the transudation
of fluid into the pia-arachnoid and cerebral systems. In a fatal case of
concussion--recently under my care--the surface of the cortex, when
exposed by operation, was obscured by a layer of œdematous pia-arachnoid
¹⁄₄ inch in depth.

Arguing from the presence of the very definite pathological changes
observed in all fatal cases--contusions, lacerations, hæmorrhages, and
œdema--one may arrive at the conclusions (1) that lesions of a similar
but less serious nature are existent in the serious but non-fatal cases,
and (2) that the prolongation of the stage of depression is directly
dependent on the presence of such lesions.

On investigating the numerous cases that come under the care of the
surgeon, certain features present themselves which are not always
readily explained on the definition of concussion as given above. Thus,
the variability of the symptoms evinced in cases of concussion admitted
into hospital are well exemplified by the following table, compiled from
a consecutive series of 50 cases admitted into St. Bartholomew’s,
diagnosed and treated as concussion:--

  =12= _cases in the hospital for 7 days or less_ (_cerebral shock
  only_).

  _Temperature_ on admission: 8 subnormal.
                              2 normal.
                              2 slightly raised.

  _Pulse_ on admission: 3 subnormal.
                        3 normal.
                        6 accelerated.

  =26= _cases detained for 7 to 10 days_ (_probably cerebral shock
  only_).

  _Temperature_ on admission:  6 subnormal.
                               9 normal.
                              11 slightly raised.

  _Pulse_ on admission:  4 subnormal.
                        12 normal.
                        10 accelerated.

  =9= _cases detained for 14 to 21 days_ (_probably cerebral
  contusion_).

  _Temperature_ on admission: 2 subnormal.
                              3 normal.
                              4 slightly raised.

  _Pulse_ on admission: 6 subnormal.
                        1 normal.
                        2 accelerated.

  =3= _cases detained for 21 to 30 days_ (_certainly cerebral
  contusion_).

  _Temperature_ on admission: 1 normal.
                              2 slightly raised.

  _Pulse_ on admission: 1 subnormal.
                        1 normal.
                        1 accelerated.

Still, when all is considered, concussion and compression are but
ill-defined from one another, both in their clinical and pathological
aspects. The more indefinite cases of concussion are probably such as
border on compression, the increasing œdema gradually carrying the
patient across the border line between the two conditions.

In the present state of our knowledge respecting concussion or cerebral
shock it may, I think, be accepted (1) that concussion is dependent on
an acute inhibition or paralysis of the vaso-motor centre; (2) that the
milder cases are unassociated with any pathological visible changes; (3)
that the prolongation and severity of the depression stage are directly
proportionate to the extent of the brain lesion, such lesions varying
from œdema and contusion to extensive hæmorrhages and lacerations.


Its symptomatology.

_The stage of depression._ The symptoms are evoked immediately on the
receipt of the blow, the patient falling to the ground from lack of
muscular control and loss of consciousness. The muscular system is
completely relaxed, the limbs, when raised, falling helplessly to the
ground. The face is deathly pale, the eyes usually open, fixed, and
expressionless, the pupils equal, commonly dilated and responsive to
light. The patient _may_ be aroused by strong stimuli--pinching,
shouting in the ear, pressure over the supra-orbital nerves, &c.

The pulse is small, slightly accelerated, and occasionally intermittent.
The respiration is weak, shallow, and often irregular. The temperature
is lowered, sometimes to such an extent that it cannot be registered on
the thermometer. The surface of the body is cold and clammy, beads of
sweat standing out on the brow. The deep reflexes are abolished. Some
attempts may be made at swallowing when fluids are placed in the mouth.

Urine is often expelled at the time of the accident, and, more rarely,
fæces may also be passed involuntarily.

The condition either gives place to that of reaction or the state of
unconsciousness and collapse becomes more profound, in which case the
prognosis is most unfavourable.

_The stage of reaction._ Weak, purposeless movements are observed and
the patient may sigh heavily, mutter, or groan. This is followed by
profuse vomiting, after which the temperature begins to rise, the body
becomes warmer, and the patient recovers his senses either entirely or
in part. The heart beats strongly, the pulse being full and slightly
accelerated in rate. The carotid arteries are seen to pulsate forcibly,
the face is flushed and moist. The patient is restless, and complains of
severe headache, due in all probability to intradural hypertension.
Under efficient treatment these symptoms of cerebral hyperæmia abate,
the patient recovering quickly or slowly, according to the severity of
the blow. Retrograde amnesia is often a conspicuous feature in the more
severe cases, varying greatly in depth and character, seldom permanent.

In the more serious cases--those associated with severe cerebral
injury--the pupils dilate fully and do not react to light. Corneal
reflex is absent. The medullary centres gradually become exhausted, the
pulse becoming smaller, increasing in rapidity, and finally
unrecognizable. Respiration becomes weaker and often Cheyne-Stokes in
character. Respiration ceases before the heart gives out.


Cerebral Irritation.

_Its pathology._ Sufficient evidence is supplied, both by clinical
symptoms and by post-mortem examination, to show that brain irritation
is dependent on definite brain lesions, these varying from ‘bruising’ to
minor degrees of laceration. Bruising or contusion of the
brain--evidenced by pia-arachnoid hæmorrhages and by cortical and
subcortical hæmorrhages--is most prevalent in the frontal and
temporo-sphenoidal regions. The same may be said with respect to
laceration.

_Its symptomatology._ From the initial stage of concussion the patient
passes into that of irritation, the reaction being of a rather violent
type and accompanied by considerable rise of blood-pressure.

The patient lies curled up in bed, the lower extremities flexed at the
hip and knee, the upper limbs bent across and partially covering the
forwardly flexed head. He is exceedingly restless. Restraint is usually
required. The eyes are tightly closed, and all attempts at pupillary
examination are strenuously resisted. The patient groans, mutters, and
uses language, perhaps suited to the occasion but not adaptable to
polite society. Headache is severe, often referred to the frontal
region. The skin is hot and dry--burning--the body temperature is raised
whilst the pulse is accelerated and its tension increased. Both urine
and fæces may be passed into the bed, not so much from loss of bladder
and rectal control as from transitory moral perversion.

The state of irritation subsides or merges into that of cerebral
compression.


Compression.

_Its pathology._ A compression force--whether foreign body, blood
extravasation, abscess or tumour--must act on the brain substance or on
the fluid constituents of the skull. The brain, however, is itself
incompressible. It may be squeezed like a sponge, but its actual
structure is unalterable. Consequently, the compressing force exercises
its main influence on the fluid contents, driving out the cerebro-spinal
fluid, depleting the cerebral veins and emptying the arterioles,
producing in other words a state of brain anæmia.

Experimentally, it has been ascertained that from 3 to 6 per cent. of
the cranial capacity can be taken up by a foreign body without producing
compression symptoms--probably owing to the escape of cerebro-spinal
fluid into the spinal canal, and the recession of the medulla and
cerebellum into the foramen magnum. Furthermore, it would appear that
the incidence of compression symptoms is associated with depletion of
those cerebral veins which are in closest relation to the compression
force. As this force increases--for example, in middle meningeal
hæmorrhage--the pressure exercised on the surrounding regions increases
proportionately, to the level of the capillary pressure, and even to
that of the smaller arteries. A state of cerebral anæmia results, first
localized to the region primarily involved, then invading more widely
and finally affecting both supra- and infra-tentorial spaces.

With regard to the continuity of pressure between these three spaces,
there is but little pressure discontinuity between the two
supra-tentorial spaces, whilst, between the supra- and infra-tentorial
regions, there is less ready communication.

A slight degree of compression in the supra-tentorial space will act on
the corresponding space only, greater degrees will involve all three.
On the other hand, a rise of infra-tentorial pressure is not of
necessity associated with a corresponding elevation in the other two
regions. For example, a cerebellar tumour readily affects the medullary
centres, whilst the higher cortical regions are for the time being
totally unaffected. Again, a tumour situated in the frontal pole does
not necessarily produce any of those symptoms of cerebral compression
which are regarded as referable to an increase of subtentorial
pressure--slow pulse, vaso-motor disturbances, subnormal pressure, and
deep rhythmical respiration.

Returning once more to the vascular effects of a localized compression,
it is obvious that whilst the compressing force is producing a
surrounding anæmia--depleted veins and arterioles--yet that the
neighbouring but more distant brain is venously engorged--from venous
retardation. Insomuch, moreover, as the venous tension and
cerebro-spinal pressure are equal, it is obvious that, as the result of
venous engorgement, there is some surrounding serous transudation into
the perivascular, pia-arachnoid, and cerebral regions. The brain
bordering on the anæmic area is therefore œdematous, the œdema
diminishing and fading away in direct proportion to the distance of the
area involved from the primary focus of compression.

If the compression force is of a progressive nature, the engorged area
becomes in turn anæmic, and still more distant regions become engorged
and œdematous. This state is known as that of _progressive œdema_. Its
complete development is largely dependent on brain infection--abscess of
the brain, &c.

The rapidity with which the symptoms of compression develop are largely
dependent on the producing cause. Thus, three examples may be cited:--

(1) Compression of slow development, requiring weeks or months before
typical symptoms are observable--e. g. tumour formation.

(2) Compression of medium development, requiring days only: e. g.
abscess, subdural hæmatocele, and some forms of middle meningeal
hæmorrhage.

(3) Compression of acute development, almost immediate: e. g. diffuse
subdural hæmorrhage, some cases of middle meningeal hæmorrhage,
depressed fractures, and intracranial foreign bodies.

The special symptoms of compression are, as Leonard Hill pointed out,
referable to the effects produced on the bulbar centres. That such is
the case is suggested by the following facts:--

(1) The same compression symptoms result wherever the compressing force
acts.

(2) Experimentally, an increased pressure in the posterior fossa
produces compression symptoms earlier than when the compressing force is
exercised in some more distant region of the brain.

(3) A fracture involving the posterior fossa gives rise to compression
symptoms earlier than a fracture in some more distant region.

(4) A far smaller body kills in the bulbar region than in the cerebral
chamber.

(5) The general pressure effects are in no way due to excitation of the
part of the brain pressed on, for, after division of the mesencephalon,
the pressure was just as active in calling forth changes in respiration
and circulation (Sir Victor Horsley).

Leonard Hill also pointed out that the first effect of anæmia of the
bulbar region was in the nature of stimulation, the vaso-motor centre
being influenced in such a manner as to produce a general rise of
blood-pressure. A further degree of compression may again produce the
same result, the arterial pressure rising considerably above the normal.
Later on, the medullary centres--and more especially the
vaso-motor--become exhausted, with consequent grave fall in
blood-pressure. The pulse, previously slow and full, becomes rapid,
small, readily compressible, and irregular in rhythm, whilst the
respiration, previously deep and regular, becomes gasping, irregular,
and Cheyne-Stokes in character.

The sequence of events may be depicted in another manner. In cerebral
compression, the battle--as pointed out by Schüster--largely resolves
itself into a life and death struggle between the attacking compression
force on the one hand and the defending vaso-motor centre on the other.

Up to a certain point the vaso-motor centre holds the whip-hand. The
capillary anæmia as produced by the compression force--cerebro-spinal
tension, &c.--brings about a condition which not only acts as a stimulus
to the vaso-motor centre but also exercises a marked effect on the
vagus and respiratory centres. The blood-pressure rises, the pulse is
slowed in rate, and its tension markedly increased, whilst the
respiration is slightly irregular both in depth and rhythm. The
vaso-motor centre thus attacked sends out further impulses so as to
raise the blood-pressure to slightly above requirements. The bulbar
centres are again flushed with blood, the vaso-motor centre ‘slacks
off’, and the blood-pressure falls again.

The compressing force is, however, still active and full of fight. A
further capillary anæmia results. The vaso-motor centre again responds
and the blood-pressure rises higher than ever, the pulse-rate is further
slowed, and the respiration is deeper, less regular, and even
stertorous.

This combat continues, and, in the presence of an active compression
force, there is that rhythmic activity of the vaso-motor centre which is
represented by the well-known Traube-Herring curves; again, the height
to which the vaso-motor centre drives the blood-pressure may be taken as
representing the activity of the compression force.

When the compressing force rises above a certain limit the _débâcle_
occurs--the vaso-motor centre retires from the fight, there is a rapid
fall in blood-pressure, the medulla is emptied of blood, and both
cardiac and respiratory centres share in the defeat (rapid pulse of poor
volume and Cheyne-Stokes respiration).

These being the effects as exercised by compression on the bulbar
centres, one must not omit to consider the results produced on the
higher cortical centres. Anæmia is the feature and unconsciousness is
the ultimate result, preceded by headache and drowsiness progressing on
to stupor and coma. Intermediate between the stages of sleepiness and
coma, one observes occasionally a stage of irritation--such as is
pictured in many cases of typical middle meningeal hæmorrhage.

In fatal cases the respiratory centre gives out first, the heart often
beating for some time after all attempts at respiration have ceased. In
a case recently under my care, respiration ceased during the process of
trephining. The patient was kept ‘alive’ for three hours by means of
artificial respiration, and under such mechanical breathing the patient
retained a good colour and the heart worked well. So soon, however, as
efforts were relaxed, the pulse became weaker and weaker until further
artificial respiration again restored the balance. This process was kept
up till it was realized that the respiratory centre was ‘dead’.

From these facts, it may be assumed that the special symptoms of
compression are dependent (_a_) on anæmia of the bulb--with
corresponding cardiac, respiratory, and vaso-motor changes; and (_b_) on
anæmia of the cortex--with unconsciousness.

=Its symptomatology.= According to Kocher, the following are the four
stages of compression:--

1. _The stage of compensation._ A mild degree insufficient to seriously
compromise the circulation. Cerebro-spinal fluid escapes into the spinal
canal and some of the venous radicles are compressed. Some venous
engorgement. Some headache, possibly some focal symptoms. Some mental
dullness.

2. _Stage of beginning compression._ Beginning failure of the
circulatory compensation. Headache pronounced, vertigo, restlessness,
excitement or delirium. Objective symptoms of venous stasis--dilatation
of the veins of the eye, both external and internal, œdema of the disk.
Affection of the medullary centres, shown by a slowed pulse and a slight
rise in temperature.

3. _Stage of fully-developed compression._ Widespread capillary anæmia.
Medulla affected markedly. The period of vaso-motor regulation has set
in with its high blood-pressure, and this, with its vagal quality, gives
the pulse its bounding character. The rise in blood-pressure shows a
definite rhythm. Also rhythmicities in respiration which may acquire the
Cheyne-Stokes character. Rhythmic alterations in the size of the pupils,
with alternate increase and decrease in the depth of stupor, so that the
‘up-wave’ causes the patient to moan, become irritable, and thrash
about, whilst the ‘down-wave’ sees him completely comatose. Pulse is
markedly slowed and the disks evidence pronounced ‘choking’. Reflexes
are abolished, cyanosis extreme, respiration snoring.

4. _Stage of paralysis._ Irregular cardiac and respiratory efforts,
pulse grows rapid, coma deepening, muscular relaxation, pupils widely
dilated, and permanent fall in blood-pressure. Respiratory paralysis.


Treatment.

(_a_) _Of concussion._ In considering the treatment of concussion, it
has to be remembered that we are treating a condition dependent on
vaso-motor depression, and that we are ignorant--at any rate for the
time being--as to the nature and extent of a possible cerebral lesion.
It is obvious, therefore, that although we are clear as to the general
lines on which treatment is to be carried out, yet that our earlier
methods must be expectant and our subsequent methods symptomatic. In
other words, we must be prepared, at any moment, to change the method of
treatment according as symptoms demand.

The more general treatment--applicable to all cases, of whatever
severity--consists in putting the patient to bed with the head low, in
the application of warmth to the body and extremities, and in the
administration of hypodermic injections of morphia, a drug of great
value in the more severe cases of concussion. It must, however, be
administered with caution, lest important symptoms be masked.

Strychnine and brandy are practically useless. They merely whip the
willing horse--the heart is doing full duty and cannot be further
stimulated by such measures.

In _mild and moderately severe cases_ this form of treatment will
suffice to tide the patient over the collapse stage and induce the stage
of reaction. So soon as this _commences_, the rising temperature and
vomiting heralding the change, the head of the bed should be lowered,
hot bottles and blankets removed--the patient being covered with a linen
sheet only--and all forms of stimulant avoided.

Calomel should be given by the mouth, 1 to 5 grains, according to the
age of the patient. Headache may be relieved by applying ice-bags to the
head, by tying round the forehead a handkerchief soaked in a weak
solution of eau-de-Cologne, and by the administration of various drugs,
more especially aspirin (10 grs.), antipyrin (10 grs.), and hyoscin (gr.
¹⁄₁₀₀).

In _more severe cases_ more radical measures must be adopted to combat
the severe vaso-motor depression, with its consequent splanchnic
congestion and cerebral anæmia. No method is more desirable than
infusion. This method, with its attendant advantages and disadvantages,
has been detailed on p. 118. It is merely necessary to add that infusion
must not be carried out in a haphazard manner. Its application is based
on scientific principles, and its results must be noted with the
greatest care. The surgeon must keep a watchful eye on the temperature
and blood-pressure, and he must be prepared at any moment to change his
plan of campaign.

(_b_) _Of irritation._ The patient should be kept in a darkened room and
should not be worried more than is absolutely necessary for diagnostic
purposes. An attendant is usually required, whose methods should be
persuasive rather than forcible. Great tact is required.

Morphia is of the greatest value in the treatment of this condition. It
relieves the headache, acts as a damper on the hyperæmic brain, and
keeps the patient from threshing about in bed and injuring himself.
Sleep is essential for an early recovery and cure.

In the _more severe cases_ venesection should be carried out, and
operative measures will be required if the rising temperature and slowed
high-tension pulse herald the advent or indicate the presence of
compression of the brain.

(_c_) _Of compression._ The various operations carried out for the
relief of compression of the brain are discussed elsewhere. They include
such operations as are conducted for localized hæmorrhages, whether
subdural or extra-dural (see Chap. V), and such also as are described as
‘decompression’ operations (see p. 121).

With regard to the general indications for adopting active surgical
measures, the surgeon is, of course, guided in his estimation of the
case by the general condition of the patient--depth of unconsciousness,
&c.--but more especially by the temperature changes and alterations in
blood-pressure. In my own practice I am guided very largely by the
temperature changes--as described on p. 114. On the other hand, some
surgeons pin their faith more especially on the blood-pressure changes.
Thus Archibald writes: ‘If the blood-pressure be 130 mm. Hg. on
admission, an hour later 150, still later 200 or 250, we are immediately
in possession of the fact that the available intracranial space is being
steadily, dangerously reduced, and that the vaso-motor centre is
straining every nerve to stave off defeat.’

I am, of course, ready to concede the great value of blood-pressure
tracings, but, in my experience, the temperature changes have been even
more consistent, so much so that I base my treatment of a case very
largely on such changes. One word of warning--the temperature must be
taken every half-hour, and active surgical measures adopted _so soon as_
the rising temperature, slowing high-tension pulse, and deepening
unconsciousness point to advancing compression.

There is undoubtedly a growing tendency amongst those who have carefully
studied the effects of trauma on the skull and brain to carry out
exploratory and decompression operations at an early period, even in
cases which present no symptoms of special localizing significance. The
pathological conditions so commonly found and the excellent results that
have been obtained prove that the adoption of early surgical treatment
is founded on a very sound basis.


=Points in the differential diagnosis between traumatic and other forms
of coma.= The previous history of the case, the nature of the accident,
and the lesions found may enable the surgeon to arrive at ready
diagnosis. Often, however, it is impossible to exclude non-traumatic
forms of coma without an exhaustive examination of the patient. In the
process of examination, it is convenient to have in one’s mind a simple
memoria-technica. Thus,

  A stands for Alcohol and Apoplexy.
  E    „    „  Epilepsy (post-epileptic coma).
  I    „    „  Injury.
  O    „    „  Opium poisoning.
  U    „    „  Uræmia.

To this list must be added Diabetic Coma.

Having these conditions in mind, the patient is examined from head to
foot in the following manner:--

The _vault of the skull_ is first examined and all evidence obtained as
to the presence and extent of external injury.

The _ears and nose_ are investigated for escaping blood or
cerebro-spinal fluid, important symptoms in the diagnosis of fracture of
the base.

The _eyes_ are next examined. Ocular palsies suggest injury or apoplexy;
hæmorrhages--subconjunctival or palpebral--point to injury; whilst the
condition of the pupils and disks may offer valuable information. Thus:

In concussion, the pupils are equal, dilated, but responsive to light.

In irritation, they are equal but contracted.

In compression, they are either equal, dilated and fixed, or unequal.

In alcohol, they are more or less normal, except in the deeper stages of
intoxication, when they are dilated and irresponsive to light.

In apoplexy, dilated and fixed, or unequal. Pin-point in pontine
hæmorrhage.

In epilepsy, usually equal and responsive.

In opium, immovably and symmetrically contracted.

In uræmia, dilated and sluggish.

In diabetes, equal but dilated. React to light.

In doubtful cases an examination of the disks may clear up the
diagnosis. The presence of albuminuric retinitis, optic neuritis and
atrophy (diabetes and uræmia), retinal hæmorrhages (injury), offer
material diagnostic aid.

The _tongue_ should be examined for such biting as is observed in
epilepsy. The odour of the _breath_ is investigated--the sickly smell of
alcohol, the sweetish odour of uræmia, the peculiar smell of opium, the
chloroform-like smell of diabetes.

The appearance of the _face_ may be suggestive. The unilateral facial
palsy of trauma and apoplexy; the stertorous respiration, puffing out of
the cheeks, and general turgidity of compression, uræmia, apoplexy and
deep alcoholism; the quiet breathing and pale face of concussion, opium
poisoning, and of post-epileptic and diabetic coma.

The _urine_ should be examined for albumen and sugar, and the body and
lower extremities for œdema.

The _extremities_ are investigated with respect to unilateral palsy, a
condition only present in trauma and apoplexy. General convulsions point
to injury, uræmia, and epilepsy. Resistance to manipulation is
suggestive of alcoholic excess. Unilateral palsy may be associated with
corresponding alteration in the deep reflexes.

The _pulse_-rate and the condition of the arteries supply valuable
evidence. The coats may be atheromatous, whilst the slow, full pulse is
strongly suggestive of compression, apoplexy, and alcoholism.

The _temperature_ should be taken on both sides of the body. A rise of
temperature is usually dependent on brain injury, apoplexy, and
alcoholism. In opium poisoning, uræmia, and epilepsy the temperature is
more likely to be normal or subnormal. In pontine hæmorrhage,
hyperpyrexia is commonly observed.

Some difference in the temperature on the two sides of the body points
to injury or apoplexy.

The _depth of the coma_ is often of the greatest assistance in the
differential diagnosis. Thus, in concussion, alcohol poisoning, and in
the minor grades of epilepsy and uræmia, the patient may often be
sufficiently aroused by shouting in the ear, digital pressure over the
supra-orbital nerves, or by the application of the battery, as to give
some account of the accident, &c. In compression, in the deeper states
of uræmic and diabetic poisoning, and in the status epilepticus, the
patient can seldom be aroused from the deep coma into which he is sunk.

In all cases of doubt the patient must be kept under careful
observation.

[26] _Syst. of Pract. Surg._, vol. ii.

[27] _Deutsche Zeit. für Chir._, Bd. 4, vols. i and iii.

[28] _Guy’s Hosp. Reports_, 1885-6.

[29] Bergmann’s _System of Surgery_, vol. i.

[30] _Ruptures de l’Artère méningée moyenne._

[31] _Guy’s Hospital Reports_, vol. lix.

[32] _Traumatic Injuries of the Brain._

[33] _Traumatic Injuries of the Brain_, p. 138.

[34] _System of Surgery_, vol. i, p. 179.

[35] _American Practice of Surgery_, Bryant and Buck.




CHAPTER VI

THE REMOTE EFFECTS OF HEAD-INJURY


=General considerations.= It is often stated that a patient who has
received a severe head-injury is ‘never the same man afterwards’. Before
accepting such a sweeping statement--the gravity of which is obvious--it
is essential that an extensive survey should be made into the remote
effects of head-injury, and, in their consideration, the surgeon must
not be biased by those cases that seek hospital relief. It is the
unfavourable cases that present themselves for examination, the more
favourable are usually lost to view. Furthermore, whether the early
results are completely satisfactory or not, but little guide can be
obtained into the more remote results unless, as a routine procedure, an
attempt be made to trace all such cases in their after-history. The more
remote results can then be estimated at their true value.

The difficulties attendant on all attempts at following up hospital
cases are considerable, and consequently we are greatly indebted to
Crisp English[36] for his tabulation and discussion on the after-history
of 300 cases treated at St. George’s Hospital--300 cases personally
investigated at periods varying from one to twenty years subsequent to
the time of the injury.

English’s conclusions have been compared with those derived from my own
personal experience, with the result that they were found to coincide so
closely that they may be accepted as affording an accurate guide into
the remote results of head-injury in general.

English classified his cases into three series--each 100 in
number--according to the severity of the lesion.

Series 1. Fracture cases.

Series 2. Cases of concussion, contusion, and laceration.

Series 3. Miscellaneous cases.

The remote results as observed in the first and second series were as
follows:--

  Series 1.  No effects       31
             Slight effects   50
             Marked effects   19

  Series 2.  No effects       48
             Slight effects   42
             Marked effects   10

In the 200 cases, therefore, that come under Series 1 and 2, 79
experienced no ill effects from the injury, 92 developed slight effects,
and definite defects were present in 29 cases.

Before alluding further to the mental and bodily condition of the
patients subsequent to the accident, including their wage-earning
capacity, it is necessary to enlarge on the fact that the depreciation
in mental and physical faculties depends, not only on the severity of
the injury, but also on the age, disposition, and status of the patient.


_The effect of age._ All evidence tends to prove that head-injuries in
the young and the old are more serious than when the accident occurs
during middle life. In the old, the power of repair is impaired; in the
young, the developing faculties are impeded in their progress.


_The effect of disposition._ The temperament of the patient must always
be taken into consideration, the neurotic type seldom recovering so
quickly or so completely as the more plethoric.


_The effect of status._ A complete recovery is far more likely to occur
when the status of the patient allows of complete rest, bodily and
mental, for some considerable time subsequent to the accident. A
premature return to work, with possible added family troubles,
invariably acts as a deterrent to complete recovery. In the milder cases
a few weeks suffice to allow of restoration to health, in other cases an
interval of at least one year should be allowed before the patient again
takes up his duties. It is obvious, therefore, that family troubles and
business emergencies influence to a marked degree the completeness of
recovery. It might be anticipated that the financial necessities of the
case would cause the various after-results of head-injuries to be more
marked amongst the labouring classes. The personal equation, however,
enters largely into the question, and due allowance must be made for the
greater financial and social losses entailed when the injury involves
one who occupies a high social sphere. It must also be borne in mind
that those occupying such spheres may not benefit from the Workmen’s
Compensation Act.

On referring again to English’s cases, it was found that the
wage-earning capacity of the patient afforded a valuable clue in the
estimation of the remote results in general. Thus in Series 1 and 2 the
following results were obtained:--

Series 1. 86 cases:

  52 carried out the same work at the same wages.
  13 carried out lighter work.
   7 could do but little work.
   8 had to take to other work, less dangerous.
   6 were totally disabled.

Series 2. 78 cases:

  51 carried out the same work at the same wages.
  12 worked as before, but without much interest.
   6 were compelled to undertake lighter work.
   4 could do a little work.
   2 gave up their trade for another, less dangerous.
   3 were totally disabled.

Thus 59 per cent. in Series 1 and 80 per cent. in Series 2 were able to
do the same work at the same wages as previous to the accident.

It will be of interest to compare English’s results with those obtained
by other investigators. Thus, in 48 cases examined by Graf, the
following results were obtained:--

  In  9 cases, no bad results.
     10 cases, slight troubles or impaired work-power.
     12 cases, limited power of work.
     17 cases, complete incapacitation from work.

Thus 35 per cent. of cases were completely incapacitated from work,
results far more serious than according to English’s investigations.

Again, Crandon and Wilson made inquiries into the after-effects in 38
cases, with the following results:--

                      _Yes._    _No._
  Headache              13       25
  Eye troubles          17       21
  Dizziness             15       23
  Deafness              16       22
  Paralysis              1       37
  Faints                 4       34
  Fits                   2       36
  Loss of memory         4       34
  Troubled by the sun   13       25
  Troubled by alcohol    6       32

On investigating those cases reported by English, in which the patient
was compelled to take on lighter work or change his vocation, one at
once encounters a diversity of symptoms, some so indefinite as to be
included under the term traumatic neurasthenia, others so distinct as to
fall naturally under certain well-recognized groups, such as traumatic
cephalalgia, epilepsy, &c.


=Traumatic neurasthenia.= All those cases characterized by the
indefinite nature of their complaint require the most careful
sifting--to separate the wheat from the chaff--for there is always a
certain proportion of malingerers, such as realize the pecuniary
advantages of their position. When these are excluded, a large class
remains in whom the injury must undoubtedly be regarded as the _fons et
origo mali_. A curious and interesting train of symptoms supervene after
the accident, indefinite from a localizing point of view, but quite
definite from the standpoint of the patient himself. Mental
irritability, with a ready tendency to fly into a passion--Kaplan’s
explosive diathesis--may be regarded as an almost constant symptom. The
patient is changed in his manner towards those near and dear to him,
restless, irritable, and intolerant of noises, morose, and incapable of
managing his financial affairs.

The change may be insidious in origin, but, in the absence of
appropriate treatment, steadily progressive. The mental changes, unless
checked in time, tend to merge into definite insanity, not infrequently
of a homicidal or suicidal character.

Insomnia, with terrifying dreams, loss of appetite, emaciation,
headache, vertigo, nervousness, amnesia, lack of power of mental
concentration, and mental depression are all noticeable features. All
such symptoms are aggravated by indulgence in alcohol, exposure to the
sun, &c.

From a localizing point of view the symptoms are obscure, but they are
probably none the less dependent on pathological changes--thickening of
the meninges, effusion into the subdural and subarachnoid spaces, œdema
of the cortex, &c. Furthermore, it will usually be found that, during
the height of the attacks, the pulse-rate is slowed, the temperature
raised, and the respiration embarrassed--symptoms suggestive of
cerebritis and alterations in the intracranial pressure.

In exploratory operations conducted in cases of this nature, I have been
particularly struck by the fact that in a large proportion of cases one
finds what appears to be a condition of local œdema--some fluid beneath
the dura mater, and a greater excess of the same in the pia-arachnoid
meshwork. This œdema is a manifest condition readily demonstrated to
onlookers. I am not an advocate of ventricular puncture in these cases,
mainly on the ground that it complicates the operation and brings no
added benefit in its train, but in such cases as it has been carried out
the jet of cerebro-spinal fluid proves the added existence of an
increased intraventricular pressure. From Leonard Hill’s experiments it
would appear that this œdema is dependent on chronic vascular
changes--arterial anæmia, venous congestion, and cerebro-spinal and
serous accumulation.

At a later date the meninges may become thickened and adherent to one
another and to the surface of the brain, whilst false membranes and
arachnoid cysts may develop.


=Treatment.= For these more general and indefinite remote results of
head-injury the treatment comprises REST, bodily and mental, light diet,
fresh air, cheerful but quiet surroundings, and encouragement. Potassium
iodide and mercury (preferably by inunction) often do good, whilst
phenacetin and antipyrin are perhaps the best drugs for relief of
headache. For sleeplessness potassium bromide is perhaps the best
remedy.

I have found in some cases that Turkish baths and massage have brought
about considerable improvement. In advising such energetic treatment the
surgeon must be guided by the case before him, these measures being more
or less restricted to the less serious and more chronic cases.

In the more serious cases, especially when slowing of the pulse during
the height of the attacks and some blurring of the disks point to a
probable increase of intracranial pressure, operative measures must be
considered. The greatest circumspection is required in determining the
class of cases in which operation may be proposed, and the surgeon must
be most guarded in his prognosis. So far as my personal experience goes,
the operation has invariably brought about some amelioration in the
condition of the patient, whilst now and again a complete cure may be
anticipated. Those cases which on exploration evidence an œdema of the
brain are the least favourable; those in which the surgeon finds a
subdural cyst or hæmatoma offer the best prognosis.

With respect to the details of the operation, two courses are available:
(1) examination of the meninges and brain at the seat of injury, and (2)
a ‘decompression’ operation. The former course should be adopted
whenever the local conditions are favourable, that is to say,
whenever depression or absence of bone, localized headache, &c.,
suggest a localized lesion. Under other circumstances Cushing’s
intermusculo-temporal method of decompression should be carried out.
This operation should be conducted first over the right temporal region,
thus avoiding all possibility of inclusion of Broca’s area, a similar
operation being done on the left side at a later date in the event of
incomplete success.


=Traumatic cephalalgia.= Of all the after-results of head-injuries,
headache is the most constant symptom, either localized to the region
primarily involved or diffuse. Even when diffuse, however, the aching is
frequently referred to the frontal region. Localized headaches are the
more acute. The patient can place his finger over the site of the
trouble with accuracy and constancy. Examination on the part of the
surgeon causes him to wince or cry out. Percussion with the tip of the
finger not only leads to marked exacerbation but also induces a dull
aching sensation, which lasts for some time afterwards. Whether acute or
dull, exacerbations are of frequent occurrence, and during these
attacks the patient is entirely incapacitated, desiring nothing more
than to be left alone.

In some cases the pain is referred along the course of one of the
superficial nerves, in which case it is probable that the affected nerve
is caught up in the scar.

Headache, of whatever nature, is increased by exertion, indulgence in
alcohol, exposure to the sun, &c.

Crisp English considers that many cases of localized headache are
dependent on a localized chronic osteitis, and recommends trephining and
removal of the affected bone. There can be no doubt that the mere
removal of a disk of bone will occasionally bring about a cure, but,
from my own experience, I take a different view with respect to the
pathological lesions present. I have operated on over a dozen cases of
chronic cephalalgia, and I have found in nearly every case definite
pathological lesions--depression of internal table, thickening of the
meninges, subdural cysts and subdural hæmatomata. The mere removal of a
disk of bone may relieve the symptoms by reducing the local pressure or
by removing a source of meningeal irritation, but such treatment seldom
brings about permanent relief. The dura mater should be opened in nearly
every case, the frequent discovery of a subdural complication--cyst or
hæmatoma--showing that such a course is necessary.

These patients suffering from chronic headache are often pitiable
subjects, spending their time in wandering from doctor to doctor, from
hospital to hospital, seeking relief. They are only too eager to obtain
benefit from surgical intervention. The greatest care is required in
deciding as to operative procedures. Injudicious surgical measures are
not only disappointing to both surgeon and patient, but also
discreditable to this branch of surgery. On the other hand, it must be
acknowledged that remedies other than surgical are generally
inefficacious. The surgeon, therefore, takes considerable responsibility
on his shoulders when he states that an operation is inadvisable. Though
guarded in my prognosis, I generally advise operation on the ground that
it is impossible to foretell the cause of the headache, and brilliant
results may be obtained.


=Treatment.= When the headache is diffuse, REST, aided by the
administration of phenacetin, &c., may exercise some effect. Operative
treatment should not be recommended unless the intensity of the attack,
blurring of the disks, and slowing of the pulse suggest that there is
some increase in the general intracranial pressure. Under such
circumstances, exploration should be carried out over the region at
which the injury was received. In the absence of evidence with respect
to external injury, a subtemporal decompression operation is the
operation of election.

When the pain is localized to some special region, the outlook is more
favourable. Operative measures should then always be carried out over
the painful spot. A scalp-flap is framed according to the region which
it is desired to expose, the disk of bone removed, and the meningeal
territory examined. For detailed operative technique, see p. 20.

When the pain is referred along the course of one of the scalp nerves,
it may be relieved by alcohol injections (see p. 314), or by exposure of
the nerve, followed by removal of at least 1 inch of its trunk.


=Traumatic epilepsy.= When epilepsy arises after a head-injury, it is
almost the invariable rule that the attacks should partake _at first_ of
the focal or Jacksonian type. A case of traumatic epilepsy should,
therefore, possess the following characteristics:--

1. The fit should be preceded by some sensory or motor aura--the aura
corresponding to the region of the brain primarily involved.

2. The fit should always start by twitchings of the parts supplied by
the motor area which is in direct relation, or in close proximity, to
the site of dural or osseous lesion.

3. The fit may remain localized to the region first affected, or, as is
more commonly the case, may spread to other regions. In the latter case
the various motor areas are affected in a certain definite order,
according to their cortical arrangement. Thus, a fit arising from
irritation of the right cortical face-area leads first to twitchings,
then to convulsions, and perhaps finally to paralysis on the
contralateral face-muscles, the movements then spreading from the face
to the upper extremity, and from the arm through the trunk to the lower
extremity. When the fits become generalized, spreading to the opposite
side of the brain, the cortical areas are affected in the reverse
order.

4. The patient should retain consciousness throughout the attack.

5. The fits should not be succeeded by any paresis or paralysis.

Later on, when the fits become more frequent and severe, they lose their
typical Jacksonian characters, the various regions being affected so
rapidly one after the other that all focal symptoms tend to be obscured.
The fits are then often associated with definite loss of consciousness,
and succeeded by paresis or paralysis of the parts primarily affected.
The patient also usually complains of lassitude or headache, this
lasting some hours after the termination of the fit.

Traumatic epilepsy does not always partake of the typical Jacksonian
type. Sometimes the fits are so sudden in onset and violent in character
that, from the first, the more typical features are absent. Again, fits
of the focal or Jacksonian type do not necessarily imply that some
pathological causative agent will be found on exploration. Ordinary
epilepsy sometimes partakes of the focal type. I have myself operated on
three cases of focal epilepsy, deceived by their Jacksonian
characteristics, and found nothing abnormal. On the other hand, in all
these cases definite and permanent improvement was observed subsequent
to the surgical procedures.

It might also be added that encouraging reports are to hand, not only in
cases of idiopathic epilepsy with focal symptoms, but also in cases
without focal symptoms. A decompression operation is carried out on the
basis of Kocher’s statement to the effect that the fit is immediately
preceded by a rise of intracranial pressure, for which a safety-valve
must be supplied--such as is afforded by an intermusculo-temporal
operation of decompression. Whether Kocher’s statement is correct or
not, the fact remains that some cases of idiopathic epilepsy, without
focal symptoms, benefit considerably from operation.


=The localizing symptoms of traumatic epilepsy.= When the cause of the
trouble is situated over the motor area--the pre-Rolandic cortical
strip--the fits should commence by twitchings of the fingers, toes,
corners of the mouth, &c., according to the site of the lesion. The fits
are seldom preceded by any sensory auræ, though occasionally such may be
the case, for even at the present day some doubt exists as to whether
the precentral area should be regarded as purely motor or sensori-motor.
In other cases, the patient, without being able to state definitely his
sensations previous to the onset of the fit, may be able to foretell its
immediate development, and still more rarely he may be capable of
aborting the fit or diminishing its intensity by grasping firmly or
massaging the region of the body in which the fit first develops.

When Broca’s motor speech-area is primarily involved, the fits are
preceded by difficulty in phonation, mumbling of words and incoherence,
grinding of the teeth, &c., the fits then rapidly spreading to the parts
responsible for the movements of the muscles of face and upper
extremity.

When the fits arise from a post-central source of irritation, they are
usually preceded by well-marked sensory auræ--tinglings, burning and
painful sensations--again according to the region affected.

When preceded by sensations of taste and smell, the lesion is probably
situated over the anterior part of the temporo-sphenoidal lobe.

When by visual impressions--flashes of light, &c.--the lesion is
probably situated over the occipital lobe of the brain.


=Pathology.= The pathological conditions responsible for the development
of fits are various, resolving themselves, when fully investigated, into
two main groups: those associated with meningeal changes only, and those
accompanied by definite cortical scarring and tract degeneration.

In the event of osseous deficiency the scalp is usually more or less
adherent to underlying structures, and the gap in the skull filled with
dense fibrous tissue, which is itself adherent to the membranes of the
brain and perhaps to the brain itself.

In the absence of osseous deficiency, the cerebral irritation is usually
dependent on depressed fragments of bone, on subdural hæmatomata and
cysts, and on meningeal thickening.

In the event of cerebral degenerative changes it may be presumed,
whether there is a deficiency in the bone or not, that considerable
matting of meninges and cortex is existent with pyramidal degeneration.

In the absence of evident signs of external injury, cases of focal
epilepsy in the young require careful investigation, inquiry being made
as to difficult labour, for, as Harvey Cushing points out, ‘When we
consider the widespread lesions associated with those cases that later
on are recognizable as Little’s disease, and that presumably an enormous
number of children receive at birth some trifling injury which, from
lack of symptoms, is overlooked, may it not be that many cases of
so-called idiopathic epilepsy dating from childhood can be safely
attributed to the effects of early traumatism?’

In all these, and in other doubtful cases, before undertaking surgical
procedures, the surgeon should obtain the services of a skilled
neurologist.


=The clinical course of the case.= If a typical case of Jacksonian
epilepsy can be observed from beginning to end, many curious and
interesting features will be observed. The fits, at first typically
Jacksonian, gradually lose their typical character, becoming more
frequent and less focal in nature, the patient losing consciousness
during the fit, and the fits succeeded by weakness or paralysis of the
parts primarily involved. The general mental state of the patient
suffers proportionately--he becomes morose, despondent, irritable,
homicidal, or suicidal in tendency. How far these retrograde symptoms
are dependent on degenerative processes in the brain, and how much they
result from the moral effect of the frequent epileptiform seizures, are
questions that can only be determined by observing the effect of
treatment, surgical or otherwise. Some cases respond readily to
treatment, others are too far advanced to experience any material
benefit, some end their days in the lunatic asylum.

In any case, surgical treatment, if adopted at all, must be carried out
before definite brain-degeneration arises--such changes being evidenced
by spasticity of the limbs, exaggerated knee-jerks, &c. When such
pathological changes are existent, there can be but little hope of
benefiting the patient.

Further points in the clinical course of the case, and such also as
throw further light on the pathological conditions present, will be
obtained by a survey of 21 cases that have come under my own care or
close observation.

  _Time elapsing between the date of the accident and the first fit._
    Between 1 and 19 years    9 cases
    Within 8 months           9 cases
    After a few days          1 case
    Uncertain                 2 cases

  _Age at time of accident._
    Before 15, 12 cases. Youngest, 3 years.
    After 15, 9 cases. Oldest, 55 years.

  _Sex._
    Males 20. Females 1.

  _Conditions found on external examination and on operation._
    External examination: Depression of bone and scar, 6 cases.
                          Deficiency of bone, 3 cases.
                          Scar only, 5 cases.
                          Nil, 7 cases.

    At operation: Sclerosis of bone, 1 case.
                  Tuberculous mass, 1 case.
                  Subdural cyst or hæmatoma, 8 cases.
                  Scalp adherent to dura, 3 cases.
                  Scar in brain, 1 case.
                  Œdema of brain, 3 cases.
                  Nil found, 1 case.

Some lesion, such as might be accepted as responsible for the
development of the fits, was discovered in 17 out of 18 cases. Duret’s
experience tends to bear out the view that some pathological lesion will
be found in almost every case. In 67 cases reported the following
conditions were found:--

  Depression of bone, 27 cases.
  Splinters of the internal table, 15 cases.
  Cysts, subdural, 4 cases.
  Thickening of membranes, 7 cases.


=Operation.= When the localization of the trouble is suggested by the
presence of focal symptoms, and by a corresponding scalp- or
bone-injury, no difficulty need be experienced in determining the site
of exploration. When the fits are associated with definite focal
symptoms, but without the supplementary evidence obtained by visible
signs of external injury, exploration should be conducted over that
region of the brain from which the fits appear to emanate. In the
absence of all localizing brain symptoms, operative measures should be
carried out over the site of scalp or bone lesion.

Whatever the circumstances of the case, the preliminary details are
identical. The scalp is shaved, cleansed, the head enveloped in gauze,
and the scalp-tourniquet applied.


=The formation of the scalp-flap.= When the scalp is adherent to the
bone, the incision, carried throughout down to the bone, is made in such
a manner that the flap will not only allow of the detachment of the
scar, but will also permit of the complete exposure of the neighbouring
portion of the skull.

When the scalp is adherent to dura or brain, as the result of osseous
deficiency, the edge of the knife should be directed towards the under
aspect of the flap, and the flap carefully peeled away from the region
of the gap.


The examination of the bone.

_When no fracture is found_, the operator should trephine over the
cortical area from which the trouble appears to emanate.

_When a fissured fracture is found_, trephining is carried out where the
line of fracture cuts across that region of the brain which appears to
be involved.

_When a depressed fracture is found_, the trephine is applied in such a
manner that the circle just includes the outer segment of the
depression. After removal of the disk, the dura mater should be peeled
away from the under surface of the bone, and the whole of the depressed
area cut away with the craniectomy forceps.

_When there is osseous deficiency and when the gap is filled in with
fibrous tissue_, adherent to the margins of the gap and probably to the
dura or brain as well, it is essential that this fibrous tissue should
be freely removed. All evidence goes to substantiate the statement that
meningeal irritation is the main cause of the fits, &c.

The removal of this tissue is best carried out by beginning at the most
promising part of the gap, detaching the tissue adherent to the most
prominent portion of the bone, and exposing the underlying dura mater.
The central mass of scar tissue should then be seized with forceps,
lifted up and detached as completely as possible, both from the margins
of the gap and from the underlying dura or brain. In the more
complicated cases, where the scar tissue is adherent to dura and brain,
the most careful dissection is required, and in many instances it is
necessary to include that part of the dura mater which is incorporated
with the scar. The cerebral substance should be carefully protected (see
below).


=The treatment of the dura mater.= When the dura has not been injured
during the process of exposure, pulsating freely, and presenting a
normal appearance, preparations can be made to close in or protect the
gap in the skull.

When the membrane bulges outwards, and when, in other respects, the
indications point to an increase of intradural pressure, the dura must
be incised in a crucial manner, and further investigation carried out in
the search for a subdural hæmatoma, arachnoid cyst, or other lesion. A
hæmatoma is washed out and drained, an arachnoid cyst shelled out or
treated by excision of the parietal wall (see p. 204).

When the dura is thickened, matted, and adherent to the brain, it is
picked up at the least adherent part and carefully dissected away,
exposing the pia-arachnoid region. The surface of the brain being so
brought into view, the scalpel and dissecting forceps may be required to
remove all tags and shreds of matted tissues, this process being
continued till a reasonably healthy region has been brought into view.


=The treatment of a cortical scar.= There is no reason why a superficial
scar should not be freely removed, but, unfortunately, this procedure is
necessarily followed by the formation of another scar, at least as
extensive as the original fibroid condition. The removal of cortical
scars has therefore justifiably fallen into disrepute, and most surgeons
content themselves with an exposure of the pia-arachnoid region, the
actual cerebral substance being left intact. All bleeding must be
arrested, blood extravasation merely favouring the formation of fresh
adhesions.


=The prevention of fresh adhesions between the dura and the brain and
between the scalp and the dura or brain.= ‘It is useless to talk about
the prevention of fresh adhesions; they form in spite of anything that
may be done’ (English). With this statement, I am in complete accord. It
has been recommended that fresh egg-albumen, gutta-percha tissue, silver
foil, &c., should be inserted beneath the dura or between the scalp and
the brain. Experience shows, however, that all these substances are
useless, being invaded or surrounded by granulation tissue, and, later
on, absorbed by or enclosed in dense fibrous tissue.

The formation of adhesions between the scalp and the dura or brain can,
however, be effectually prevented by the insertion of plates, &c. (see
below).


The closure or protection of gaps in the skull.

_Indications for operative treatment._ Large defects, post-operative or
traumatic.

Small defects situated over exposed portions of the skull or over the
more important regional areas.

Both large and small defects associated with chronic headache, insanity,
Jacksonian epilepsy, &c.

Certain congenital defects in the vault.

Small defects, unless situated in exposed regions or associated with
symptoms, seldom demand protection.


Methods.

_(a) The formation of bone-flaps, derived from neighbouring parts of the
skull, from some other bone of the patient, or from the bones of a
freshly-killed animal._

_(b) The interposition of plates of some foreign material between the
scalp and the bone, or the insertion thereof into the osseous
deficiency._

_(a) Bone-flaps. The osteoplastic method of König and Müller._ Two flaps
are framed in the manner described below, and the two interchanged in
position. A ⋂-shaped flap, comprising the whole thickness of the scalp,
is turned down so as to expose the region of the deficiency, the margins
of the incision lying about ¹⁄₂ inch outside the margin of the gap. The
flap is dissected from underlying structures to which it may be
adherent, care being taken to avoid injury to the blood-vessels entering
at the base of the flap.

A second flap is framed from the scalp immediately to one side of the
first flap. This second flap corresponds in size and shape to the one
already framed, but differs in that its base points in the opposite
direction. It is also peculiar in that it consists of the whole
thickness of the scalp plus the external table of the skull. The scalpel
is carried down to the bone, and the margins of the incision retracted
in such a manner as to allow of the application of the hammer and
chisel. The external table is cut through along the line of the scalp
incision and split away from the rest of the bone. The two flaps are
now interchanged in position and sewn down with a few salmon-gut
sutures.

[Illustration: FIG. 59. THE KÖNIG-MÜLLER OSTEOPLASTIC FLAP. _a._, The
scalp-flap; _b._, The osteoplastic flap; _g._, The gap in the skull.]

The osteoplastic flap is by no means easy to frame, the external table
tending to split up during the process of separation; moreover, its
formation is confined to the upper-occipital and parietal regions of the
skull, regions where the two tables are separated by diploic tissue. In
the temporal and cerebellar regions this method cannot be adopted, and
in the frontal region the deformity and scarring act as a bar to such
operative procedures.

In suitable cases, however, good results may be obtained by this method.
Asepsis is essential to success.

Bone-flaps derived from some other bone of the patient (e. g. the
tibia), or from the bones of a freshly-killed animal (e. g. the scapula
of a dog), seldom yield satisfactory results. The gap in the skull is
first exposed, the margins refreshed, and the size and shape estimated.
The bone-graft is then cut from the other bone, suited in every respect
to the deficiency, inserted in the gap and sewn into position. The
graft, however, seldom retains its vitality, being invaded by
granulation tissue, and converted, in the course of time, into dense
fibrous tissue. Furthermore, in the event of the slightest failure of
aseptic technique, it acts as foreign body and must be removed.

The attendant difficulties and the frequent failures of these auto- and
hetero-transplantations of normal bone lead to the utilization of
decalcified, calcined, and boiled bone-plates. Between these there is
very little to choose, for, whether due to the absence of calcium salts
or the destruction of bone-cells, they merely act as scaffolding media
for the formation of fibrous tissue and are more or less completely
absorbed.

_(b) Plates of some foreign material._ The following method has been
found to give the most satisfactory results. Plates of pure annealed
silver are utilized, ⁹⁄₁₀₀₀ inch in thickness (No. 2 Birmingham metal
gauge). The plates are light and of fair malleability. Supposing now
that it is required to protect a deficiency in the vault--irregular in
shape, round or oval, it matters not--the maximum antero-posterior and
vertical diameters are measured and a piece of silver cut out, which is
about ¹⁄₂ inch greater in both diameters. The convexity of the skull in
the region of the gap is estimated and the plate hammered into
corresponding shape. This is readily carried out by placing the plate on
a heavy leaden base and hammering to the required convexity. The
convexity is regulated by the site of application of the blows, the
heavier being applied to the central or apical portion of the plate, the
weaker to the periphery. A rough general convexity is so produced. The
edges of the plate are smoothed with the file, and a few holes bored to
allow of the escape of any blood or cerebro-spinal fluid that might tend
to collect beneath.

[Illustration: FIG. 60. THE AUTHOR’S METHOD OF COVERING IN A GAP IN THE
SKULL. _s._, The scalp; _pc._, The pericranium; _p._, The plate; _g._,
The gap in the skull (inside the irregular dotted line); _sc._, The
scalp-flap.]

The plate is then boiled and applied as follows. The osseous defect is
exposed by a scalp-flap--not including pericranium--the margin of the
scalp-flap lying _at least 1 inch_ external to the margin of the
gap.[37] The flap is dissected down so that its base is situated _not
more than ¹⁄₂ inch_ below the lower limit of the gap. The pericranium is
then stripped away towards the periphery. The plate is applied so that
it rests below against the base of the scalp-flap, lies throughout
between the scalp and bone, and overlaps the margins of the gap by about
¹⁄₂ inch. The pericranium is heaped up around and over the margins of
the plate, and the scalp-flap replaced. The plate is maintained in
position by the support received from the base of the flap, marginally
by the pericranium, and generally by the reposition of the
scalp-flap.[38] In the process of time, new bone is formed by the
pericranium, this and fibrous tissue developing along the line of the
scalp incision fixing the plate accurately and firmly in position.

Needless to say, absolute sterility of the field of operation and of all
media is essential. In the event of failure in cleanliness, however
slight, it will become necessary to reopen the wound and remove the
plate. In such cases a second attempt may be made at a later date.


=Results.= The results attained by operative treatment must always be
considered under two headings: the immediate and the more remote.

The immediate results are almost always of a satisfactory nature, the
fits being more or less completely controlled, or so diminished in
quantity and quality as to satisfy both surgeon and patient. Such early
results may be regarded as the general rule, and some enthusiasts
believe that the ultimate results are equally satisfactory. However, in
following up these cases, it will be found that, in a considerable
proportion of cases, the more remote results are by no means so
satisfactory. A complete and permanent cure is seldom obtained, though
the great majority of cases evidence considerable improvement, the fits
recurring, though less frequent and less intense than previous to the
operation.

The results which may be obtained should therefore be considered as
follows:--

Cases of complete and permanent cure.

Cases of definite amelioration.

Cases in which no benefit is derived.

In 20 cases that have come under my own care, the following results were
obtained:--

Complete cure in 2.

Marked improvement in 14.

No change in 4.

Cushing reports on 128 cases of traumatic epilepsy, operative measures
being adopted in 58, 40 cases of focal epilepsy and 18 exhibiting no
localizing feature. The results were as follows:--

12 cases were free from attacks for from 1 to 5 years.

30 were greatly improved or showed some improvement.

17 exhibited no change.

2 died in status epilepticus.


=Traumatic insanity.= Traumatic insanity is closely allied to traumatic
epilepsy, occurring, as a general rule, late in the history of the case,
when the frequency of the fits and the associated disturbance of the
higher faculties breaks down the mental and moral control of the
patient.

The particular form of insanity varies according to the circumstances of
the case. Kraft Ebbing reported on 42 cases, the disease partaking of
the following types:--

  18 cases of mania.
  13 cases of dementia.
   5 cases of dementia with epilepsy.
   3 cases of general paralysis.
   3 cases of melancholia.

Of 104 cases reported by Christian,

  16 were of dementia.
  29 of mania.
  47 of general paralysis.
  12 were of epilepsy.

Mania--of a violent type--usually develops within a short time of the
accident--a few hours or days. Its development is probably dependent on
an _acute cerebral œdema_--the result of a most severe grade of
vaso-motor depression--and it is often, though not necessarily,
associated with extensive cerebral injury. There is marked engorgement
of the cerebral venous system, and considerable increase of
cerebro-spinal fluid, both on the surface of the brain and in the
ventricular spaces.

When insanity develops at a later date, of whatever variety, it is
probably dependent on definite pathological changes. Ll. Powell, Duret,
and others, after investigating the conditions, came to the conclusion
that the injury was comparatively superficial--subdural cysts and
hæmatomata, pachymeningitis, osteosclerosis, ossification of the dura
mater, &c. They also maintain--an opinion that I also hold--that the
nervous phenomena are, in most cases, due to reflex meningeal
irritation.

Ll. Powell reports on 67 cases submitted to operation, with the
following results:--

  In 41 there was mental recovery.
     12 there was marked mental improvement.
      5 there was slight mental improvement.
      4 there was no change.

Death resulted in 5 cases.

The results obtained by surgical treatment are largely dependent on the
time that has elapsed since the accident. Lapse of time is no bar to
operation, but the sooner this procedure is carried out the better for
the patient.


=Treatment.= I think that it must be accepted that, without surgical
interference, the prognosis is of the most unfavourable type. These
cases, if left to themselves, drift into the public and private lunatic
asylums, there remaining to the end, hopeless wrecks.

If such is the case--and I think that refutation is impossible--and if
it be accepted that definite pathological changes are usually present,
then it is obvious that surgical interference offers the only hope of
cure or alleviation. The surgeon must be guided by the case before him,
but, in the absence of hereditary taint, exploration should be carried
out, preferably at the site of the original injury, and as early as
possible before the advent of definite cerebral and pyramidal
degenerations.

The operative details vary according to the necessities of the case.
Thus, in acute mania, acting on the supposition that the development is
dependent on an acute cerebral œdema, the surgeon should carry out a
decompression operation. Personally, I hold the view that Cushing’s
subtemporal decompression operation (see p. 121) should be carried out
on both sides of the skull, with or without lumbar puncture.

In the more chronic cases, operative procedures are conducted over the
region injured in the anticipation of discovering depressed bone,
subdural cysts, hæmatomata, &c. The operative details peculiar to all of
these conditions are discussed in other sections.

With special reference to general paralysis of the insane, Dr. Claye
Shaw holds the opinion that a general increase of intracranial pressure
is commonly present. At his instigation, and on other occasions, I have
carried out decompression operations, but I have not been able to
satisfy myself that the patients have experienced any benefit other than
temporary. There was on each occasion a considerable excess of
cerebro-spinal fluid with surface œdema of the brain, but the ultimate
results were certainly disappointing.


MENINGEAL CYSTS

Amongst the pathological conditions responsible for the development of
epilepsy, chronic cephalalgia, &c., meningeal cysts must be regarded as
of frequent occurrence.

Traumatic meningeal cysts are varied in size, site, and structure. They
may be classified as follows:--

  1. _Cysts within the calvarium._ Between the dura and the bone.
                                   Between the dura and the brain.
                                   Within the brain-substance.

  2. _Cysts projecting through a gap in the calvarium_ (traumatic
  cephaloceles). For a description of these cysts the reader is referred
  to p. 40.


=Cysts within the calvarium.= Traumatic cysts within the calvarium,
whatever their situation, may be divided into two definite groups:--

1. Where the cyst possesses fibrinous walls (in which hæmatoidin cysts
may be deposited) and contains a grumous material. These cysts are
usually subdural in position, are dependent on the previous existence of
a hæmatoma, and are known as ‘blood-cysts’.

2. Where the cyst--often of considerable size--is lined by a thin,
shiny, membranous wall. The contained fluid is almost colourless,
closely resembling cerebro-spinal fluid, but albuminous and having no
sugar-reducing reaction. The fluid is at high tension, spurting out when
the cyst is punctured. The cyst usually lies in relation to the
arachnoid membrane. Hence the name, ‘arachnoid cyst’.

To account for the development of these ‘arachnoid cysts’ two theories
have been advanced. Firstly, that they arise as the ultimate result of a
long-continued circulatory disturbance of the vessels of the membranes
or of the cortex, with consequent local cystic accumulation of
cerebro-spinal fluid or serum; and secondly, that shrinking of the brain
occurs in the region of an injury as the result of sclerotic changes in
the cerebral substance, any contraction tending to lead to the formation
of a vacuum which becomes filled with fluid derived from the surrounding
membranes. According to this latter theory, arachnoid cysts are in
reality ‘cysts ex vacuo’.

As regards symptomatology, little need be said. Occasionally ‘arachnoid
cysts’ of considerable size have been discovered at post-mortem
examinations which appeared to have exercised no local or general
pressure effects during life. More often the cysts, whether ‘blood-cyst’
or ‘arachnoid cyst’, lead to the development of Jacksonian epilepsy,
chronic headache, and the like, and are discovered during the
exploratory operation carried out for such conditions. Occasionally they
may be shelled out entire, but it is more usual for the surgeon to
remain content with the removal of the parietal wall (see p. 195). The
results obtained by surgical treatment are sufficiently gratifying.


TRAUMATIC ORBITAL ANEURYSM

(_Pulsating Exophthalmos_)

This condition was first investigated by Rivington in 1875. Since that
date many other cases have been reported, and the following remarks are
based on the examination of the records of 26 cases, 2 of which have
come under my own care.

The nature of the trouble, the results obtained by operative treatment,
and the direct evidence supplied by post-mortem examination furnish
sufficient proof to justify the statement that the symptoms are
dependent on the formation of an arterio-venous aneurysm, the internal
carotid artery and the cavernous sinus intercommunicating by means of
one or more fistulous channels. That such a lesion may arise from direct
violence--the introduction of some sharp weapon along the upper and
inner portion of the orbital cavity---is readily comprehensible. Such
injuries are, however, of rare occurrence, and the formation of the
aneurysmal communication is usually the result of indirect violence--the
application of severe blows to the antero-lateral and lateral aspects of
the head.

In explanation, the following preliminary facts may be accepted:--

In the great majority of cases the blow was applied to the temporal
region, the patient was rendered unconscious, bleeding freely from the
ear, nose, and mouth, and remained under treatment for some considerable
time. From these facts it may be assumed that the patient suffered from
a fracture of the base of the skull--anterior or middle fossa, or both
fossæ. Evidence has already been brought forward to show (1) that the
majority of fractures involving both anterior and middle fossæ traverse
the body of the sphenoid, and (2) that the cavernous sinus is very
susceptible to injury. It was also demonstrated that the internal
carotid artery is only liable to injury in that part of its intracranial
course where it is embedded in the outer wall of the cavernous sinus.
Two instances of such a lesion have been described in the section
dealing with injuries to intracranial vessels (see p. 148, and Figs. 53
and 54).

From these facts and from the post-mortem evidence supplied by the few
cases that have come to autopsy, it may, I think, be concluded (1) that
traumatic orbital aneurysm implies a condition of arterio-venous
aneurysm with direct communication between the internal carotid artery
and the cavernous venous sinus, and (2) that the aneurysmal formation is
dependent on a basic fracture which traverses the region of the body of
the sphenoid bone.

The exact nature of the communication between the two vascular channels
may be estimated from the fact that proptosis--usually the first symptom
to make its appearance--seldom becomes apparent till one or two months
have elapsed after the accident. It would appear, therefore, probable,
that the artery is not ruptured but merely weakened at the time of the
injury, the weakened arterial wall gradually giving way before the force
of the blood-stream till a definite communication is formed between the
two channels.

The male sex, by reason of its greater liability to severe injuries, is
generally the one involved, especially between the ages of 20 and 30.


=Symptomatology.= 1. _Proptosis_--usually the first symptom to
develop--seldom makes its appearance till after the lapse of one to two
months. The eyeball is protruded in the downward and outward direction,
the main pulsating tumour presenting at the upper and inner quadrant of
the orbit. Proptosis is generally steadily progressive, and, in the most
marked cases, the globe may be almost pushed out of its socket. In any
case the ‘whites’ of the eye are unduly prominent.


2. _Aneurysmal symptoms._ The tumour pulsates synchronously with the
heart’s beat, whilst compression of the common carotid of the same side
results in cessation of pulsation and great diminution in the size of
the aneurysmal swelling. On releasing the compression force the tumour
regains its original size in two or three beats of the heart, and, for a
short time, pulsates more forcibly than before. A definite thrill is
imparted to the examining finger, and, on auscultation, a loud murmur is
heard, not only over the tumour itself, but also widely conducted over
the bones of the vault, especially along the line of the superior
longitudinal sinus. The free collateral circulation between the angular
and ophthalmic arteries permits of the involvement of vessels in the
inner orbital and upper nasal regions. This is well shown in the case
depicted in Fig. 61.

[Illustration: FIG. 61. A CASE OF TRAUMATIC ORBITAL ANEURYSM.]


3. _Pressure symptoms._ The impairment of venous flow in those radicles
which drain into the cavernous sinus is evidenced by the marked
engorgement of palpebral, conjunctival, episcleral, and retinal veins.
Obstruction to lymph flow is shown by a hazy cornea, chemosis, and œdema
of the parts surrounding the orbit. The danger thus incurred by the
cornea is rendered more serious by the inability on the part of the
patient to close the eyelids over the protruded globe. Keratitis and
sloughing of the globe are to be feared. From muscular involvement,
squints and diplopia are frequently observed. The pupil may be fully
dilated through paralysis of the third nerve.


4. _Subjective symptoms._ Defect in vision is experienced at an early
date, but perhaps the most prominent subjective symptom lies in ‘noises
in the head’, compared by the patient to the thud of a steam-hammer, the
whirring of wheels, the buzzing of bees, &c. These noises are more or
less constant, most annoying to the patient, and increased on bending
down, straining, &c.

All these symptoms tend to become more severe as time lapses, though
cases have been recorded in which the symptoms remained _in statu quo_.
In the event of failure at relief or cure, the patient runs considerable
risk of losing his sight from corneal ulceration, whilst repeated
hæmorrhages and secondary infection may place the patient in imminent
danger of his life.


=Treatment.= In the consideration of the treatment of this condition,
the results obtained in the 26 cases investigated will afford a valuable
guide.

In 4 cases an expectant attitude was adopted, the patient being kept
quiet, restricted in diet, and dosed with potassium iodide. One case
improved, two experienced no material benefit, and the fourth,
dissatisfied, discharged himself from the hospital.

In 10 cases compression was applied to the common carotid artery, with
the result that in 3 cases the conditions remained stationary whilst in
the remainder, either on account of the pain produced or from complete
failure to bring about any improvement, this mode of treatment was
abandoned in favour of ligature of the common carotid. In some cases the
carotid compression was carried out by means of tourniquets, in others
intermittent digital pressure was utilized by means of relays of
assistants.

In 18 cases the common carotid was ligatured, in 12 cases as a primary
measure, in 6 after failure of other methods. The immediate and remote
results were in all cases as satisfactory as could be anticipated.
Proptosis at once diminished, the globe receding in some cases to the
normal position, and the distressing subjective symptoms were almost
entirely relieved. In many cases the patients were enabled to return to
work.

Some defect in vision commonly persists, dependent on muscular paresis
(on account of the previous stretching), retinal thrombosis, or corneal
changes. The longer radical treatment was deferred the greater and more
distressing were the after-effects of the lesion.

According to Sattler, however, the results obtained by ligature of the
common carotid are less favourable than as stated above, and by no means
devoid of danger to life. Fifty-six cases were collected with results as
below:--

  39 cases recovered and showed marked improvement.
  11 cases experienced no benefit.
   8 cases died.

It has been urged that ligature of the _internal_ carotid artery would
suffice to bring about equally satisfactory results, combined with less
danger to life and diminished risk of secondary cerebral degeneration.
Such, however, does not seem to be the case, for the anastomosis between
the angular arteries and between the terminal branches of the ophthalmic
is so free that the results obtained by ligature of the internal carotid
appear to be unsatisfactory. Indeed, even when the larger trunk was
tied, secondary operations have been occasionally required in order to
excise some large anastomotic channel in the region of the inner canthus
of the eye and over the bridge of the nose.

From these data, the following conclusions can be drawn:--

1. That by means of rest, careful dieting, and administration of
potassium iodide in large doses, the progress of the case can sometimes
be arrested, but that much patience is required and the ultimate result
is entirely problematical.

2. That compression--digital or instrumental, intermittent or
continuous--is painful, tedious, and usually quite inefficacious.

3. That ligature of the common carotid affords the best chance of cure
or alleviation.

When should the common carotid artery be ligatured? How soon after the
development of symptoms? This depends largely on the severity of the
accident that produced the arterio-venous communication. If the blow was
severe and the depth and duration of the stage of unconsciousness of a
prolonged character, it may be presumed that the brain was injured.
Under such circumstances early ligature of the common carotid presents
an appreciable danger by reason of the development of hemiplegia on
account of the further interference with the arterial supply to the
brain. In such cases the patient should be confined to bed or kept
quiet for not less than two months, the operation being carried out when
the general condition warrants surgical interference.

In the event of early operation being imperative, periodic digital
compression of the common carotid, for a few minutes at a time, may be
carried out with the object of accustoming the brain to the proposed new
form of circulation. In ordinary cases the sooner the common carotid is
tied the better is the ultimate result.

[36] _Hunterian Lectures_, February 1904.

[37] It is absolutely essential that the scalp incision should lie some
distance away from the outer margin of the plate. Failure to adopt this
procedure impedes the healing of the wound and adds to the risk of
infection.

[38] If desired, the plate may be anchored in position by means of a few
small silver-plated screws.




CHAPTER VII

TUMOURS OF THE BRAIN


=Tumours of the brain.= Tumours may develop in any part of the cerebrum
and cerebellum, from the sheaths of the efferent nerves, from the
vascular tissues, and from the membranes of the brain. Tumours arising
from the bones of the skull are considered elsewhere (see p. 325).

The regional distribution of these tumours may be estimated by reference
to the following table[39]:--

  Cerebellum             33 cases.
  Deep or subcortical    32   „
  Precentral             30   „
  Post-central           25   „
  Extra-cerebellar       19   „
  Pontine                15   „
  Temporo-sphenoidal     13   „
  Multiple                7   „
  Fourth ventricle        5   „
  Third ventricle         4   „
  Pituitary               2   „

Schüster,[40] from an investigation of 1,000 cases, showed that
cerebellar tumours are relatively more common than cerebral, the
comparative size of the two regions being taken into account. An
examination of Paton’s table shows that cerebellar and extra-cerebellar
tumours together form rather more than 25 per cent. in 202 cases of
brain-tumour formation.


=Pathology.= Gliomata, sarcomata, and endotheliomata are the three
commonest types of tumour formation. Other forms are fibromata,
tuberculomata, syphilomata, cysts, and carcinomata.

[Illustration: FIG. 62. A GLIOMA OF THE BRAIN.]

[Illustration: FIG. 63. A SARCOMA OF THE BRAIN.]


=Gliomata= occur with almost equal frequency in cerebrum and cerebellum.
They are generally primary and single, the boundaries but ill-defined,
and the tumour is seldom amenable to radical surgical procedures.

[Illustration: FIG. 64. AN ENDOTHELIOMA OF THE DURA MATER.]

[Illustration: FIG. 65. A FIBROMA OF THE DURA MATER. Indenting the
cortex and attached to the pia-arachnoid by fine filaments.]


=Sarcomata= grow from the meninges, periosteum of cranial bones, and
from the sheaths of nerves and vessels. They are either primary and then
single, or secondary and then multiple (sarcomatosis). Sarcomata are
often more or less encapsuled, tending in the first instance to exercise
a compression force, and only in the later stages to invade the
surrounding regions. It is during this early stage of development that
the tumour is capable of removal.

[Illustration: FIG. 66. AN ACOUSTIC TUMOUR. Attached loosely to the
seventh and eighth nerves.]


=Endotheliomata= grow from the meninges of the brain. They are hard,
nodular, and, in their early stages, definitely non-infiltrating, and,
when accessible, removable.


=Fibromata= are especially prone to originate in the cerebello-pontine
angle, usually possessing a narrow stalk representing an atrophied
nerve-trunk or vascular bundle. From the frequency with which these
cerebello-pontine tumours are attached to the eighth nerve they are
often designated _acoustic_ tumours. They may be as small as a pea or as
large as a hen’s egg. In their early stages they are probably pure
fibromata, appearing as pink-red lobulated tumours. They are of slow
growth, primarily compressing the brain-substance without invasion.
Later on degenerative changes are prone to occur, with invasion of the
cerebellar substance and extension into the internal auditory canal.
Whether growing in the cerebello-pontine angle or in other parts of the
skull, fibromata are often readily removed.

[Illustration: FIG. 67. SYMMETRICAL TUBERCULOMATA. Situated on either
side of the falx cerebri above the tentorium cerebelli.]


=Tuberculomata= are most commonly situated beneath the tentorium. They
are often multiple. They cannot be considered as favourable tumours from
the surgical point of view, insomuch as they are frequently associated
with tuberculous lesions in other parts of the body and complicated by a
tuberculous infiltration of the meninges.


=Syphilomata= occur with greater frequency in the cerebrum than in the
cerebellum. Sometimes they are totally unaffected by anti-syphilitic
remedies, and, under such conditions, appear as densely hard and
definitely encapsuled tumours. These more chronic gummata are usually
cortical or subcortical in position, and, when accessible, are readily
removable.


=Cysts= are of frequent occurrence. They may be (1) of traumatic origin,
containing a grumous material characteristic of the incompletely
absorbed blood-clot; (2) of parasitic origin (e. g. echinococcus); (3)
due to cystic degeneration of a sarcomatous, carcinomatous, or gummatous
mass; or (4) simple arachnoid cysts (see p. 203). Many of these cysts
are amenable to surgical treatment.


=Carcinomata= are always secondary to cancer in other parts of the
body--more especially carcinoma mammæ. They are usually multiple, and
quite unsuited to surgical procedures.

Any of these tumours may be complicated by the presence of internal
hydrocephalus, this condition being dependent on the pressure exercised
by the tumour on the veins of Galen, or on the interference with the
normal transudation of fluid from one ventricle to another.


=Symptomatology.= The symptoms resulting from tumour formation may be
considered under two headings:--

1. _General symptoms_, dependent on the general increase of intracranial
pressure.

2. _Localizing symptoms_, dependent on local compression.

Previous to discussing the symptomatology of brain tumours, it cannot be
too forcibly urged that the surgeon is seldom justified in embarking on
an extensive operation for tumour removal except after consultation with
a neurologist. Ill-planned and ill-timed operations are usually
disastrous in their results, and little creditable to cranio-cerebral
surgery in general. On general grounds also, the symptomatology of brain
tumours, as given below, must be accepted in the light in which it is
offered, not representing the complete neurological aspect of the case,
but affording an index to general diagnosis. For further information the
reader is referred to more extensive works on brain tumours.[41]


I. GENERAL PRESSURE SYMPTOMS

  Headache.
  Mental disturbances.
  Optic neuritis, &c.
  Vomiting.
  Alterations in pulse, respiration, and blood-pressure.
  Alterations in temperature.


=Headache.= Headache is an almost constant symptom, and presumably
dependent on general or local dural tension. It may be general or
localized, intermittent or continuous, intense or comparatively mild in
character. It is the more intense when the tumour develops in the
confined space of the subtentorium, and when the tumour is of
considerable size. In young subjects, before the skull is synostosed,
some compensatory enlargement of the skull may postpone the development
of headache, or diminish its intensity.

The diagnostic value of a localized headache is rather problematical,
but, when constantly referred to some particular region and when
associated with definite tenderness on percussion, the localization of
the headache assumes considerable importance in the regional
determination of the tumour. Still, too much stress must not be placed
on the site of the pain. A cerebellar tumour may give rise to frontal
headache, and vice versa.


=Mental disturbances.= In the earlier stages of tumour development the
patient is irritable, depressed, or apathetic, shows his objection to
his fellow mortals on all possible occasions, is unable to concentrate
his attention or exhibits impairment of memory. As has rather quaintly
been observed, he appears in every sense to ‘have a weight on his mind.’
Inquiry amongst relatives will show that he has ‘changed in every way’,
or ‘is not the same man’.

Mental changes vary according to the site and size of the tumour. For
example, it has been stated that a general air of elation or
exhilaration (Witzelsucht) may be regarded as almost diagnostic of
tumours situated in the anterior part of the frontal lobe.

As the tumour increases in size, somnolence becomes the marked feature,
progressing on to stupor and coma. In rare cases, mania may develop.


=Optic neuritis.= Optic neuritis must be regarded as one of the most
constant and valuable symptoms in the diagnosis of intracranial tumour
formation. The degree to which it progresses depends more on the site of
the tumour than on its size. In general, it may be stated that it is
most constantly associated with tumours of the temporo-sphenoidal and
cerebellar regions, less common in frontal tumour formation, still less
frequent in post-central tumours, and perhaps least common in tumours of
the pons. In this last-mentioned case optic neuritis is always late in
development, and not infrequently absent throughout the whole stage of
the illness.

Primary optic atrophy only occurs when the tumour exerts direct
compression on the optic chiasma and tracts--for example, pituitary
tumours.

Paton,[42] from a series of 252 cases treated at the National Hospital,
of which 202 were accurately diagnosed, found that optic neuritis or
atrophy was present in 81·2 per cent. cases. The fundus change, though
usually bilateral, may be confined to the ipso- or contra-lateral side.
Considerable discussion has taken place as to the localizing value of
unilateral disk changes. For instance, it has been stated that a
unilateral neuritis indicates that the tumour is situated on that side
of the brain, and that when disk changes are bilateral the side which
evidences the higher grade of inflammation is the side on which
operation should be conducted. In the light, however, of the most recent
research it would appear that unilateral symptoms are not to be relied
on in establishing the localization of the tumour. Gowers[43] lays
stress on the statement that with strictly unilateral neuritis one
should always suspect a general rather than a local exciting cause.

The actual cause of the neuritis is still a matter of doubt. It is
possible that the same cause is not present in every case. Still,
sufficient evidence is to hand to justify the probability that neuritis
is dependent on the general increase of intracranial pressure--there is,
at any rate, a close relationship between the two. The cerebro-spinal
fluid is forced into and dammed up within the vaginal sheaths of the
optic nerve, leading, in the first instance, to an œdema, and later on,
to compression of the lamina cribrosa and interference with the
circulation.

The increase of intraventricular pressure may also act directly on the
optic tracts and chiasma--the anterior boundaries of the third
ventricle--the pressure being then transferred directly to the nerve
tracts.

Furthermore, the great intensity, great frequency of occurrence, and
rapid development of optic neuritis when the tumour is subtentorial in
position may be explained on the hypothesis that the rigid enclosure of
the cerebellum permits of the ready application of pressure to the veins
of Galen or to the iter, thus leading to an increase of intraventricular
pressure, this pressure being then transferred to the optic region.

The alternative theory states that the old tissue destruction and the
new tissue formation sets free certain toxic substances which act on the
optic nerve-fibres, leading to œdema and inflammation. Paton, however,
comes to the conclusion that ‘the nature of the tumour does not play any
part in determining the onset of neuritis except in so far as the nature
determines its localization’.

Whatever be the localizing value of optic neuritis, it is generally
accepted that it commences in the upper nasal quadrant.

Visual acuity is but little impaired in the earlier stages of optic
neuritis, but so soon as atrophic changes develop, diminution in the
field of vision occurs.

The pupillary changes associated with tumours of the brain are closely
connected with these fundus changes. In the early stages, the pupils may
be contracted with the object of protecting the inflamed surfaces
exposed to light, whilst, when atrophy develops, the pupils may steadily
dilate, becoming fully dilated and fixed as the atrophic changes become
fully developed.

These pupil changes must therefore be taken into consideration in
estimating the value of pupillary changes in general.


=Vomiting.= Vomiting is dependent on stimulation of the medullary
vomiting centre, or on irritation of the dura mater in the immediate
neighbourhood of the tumour. The dura is supplied by branches of the
fifth cranial nerve, the stimulus being referred to the vagus centre in
the floor of the fourth ventricle.

Vomiting is of the so-called ‘cerebral’ type. It is of frequent
occurrence, generally irrespective of ingestion of food and seldom
preceded by any nausea and retching. The attacks are often associated
with exacerbation of headache, and more rarely with some slight
elevation of temperature. The more severe the vomiting the more likely
is the tumour to be subtentorial in position.


=Alterations in pulse, respiration, and blood-pressure.= In the early
stages there is but little alteration in pulse and respiration. Later
on, the increasing intracranial pressure acts as a stimulus on the vagus
and vaso-motor centres, the pulse becomes slowed and the blood-pressure
raised. When the pressure is considerable, the slow pulse and deep, even
stertorous, respiration evidence the effect produced on the medullary
centres. In the terminal stages the imminent exhaustion of these centres
is heralded by progressive acceleration of the pulse, by great fall in
blood-pressure, and by the advent of Cheyne-Stokes respiration.

The more marked the alterations in pulse and respiration the more likely
is the tumour to be subtentorial in position.


=Alterations in temperature.= The temperature tends to remain subnormal
throughout the progress of the case, except during the terminal stages
when pyrexia is often observed. Occasional elevations of temperature
during the course of the illness may be explained by transient attacks
of ependymitis or cerebritis.

Differences of temperature on the two sides of the body may occasionally
be observed, especially when the tumour involves the basal ganglia.


II. LOCALIZING SYMPTOMS


(_A_) =To the non-excito-motor frontal region (anterior frontal).=

_Headache_ tends to be localized to the frontal region, _vomiting_ is
seldom a conspicuous feature, and _optic neuritis_ is not only rather
later in development, but also less progressive than when the tumour is
placed in other situations. If the tumour occupies the orbital aspect of
the lobe, primary optic atrophy (from pressure) may be existent on the
affected side with optic neuritis of the contralateral fundus.

The _mental condition_ is often profoundly altered and, according to
some writers, more especially so when the tumour is situated on the left
side. The quality of mental change varies considerably in individual
cases. In some there is an attitude of general suspicion, the patient
following all points in his general examination with a curious air of
suspicion, in others moral perversion is the rule, whilst in a third
group of cases a state of elation and exhilaration is the predominant
feature, a condition which, as previously stated, is said to be
pathognomonic of a tumour frontally situated.

_Anosmia_--uni- or bi-lateral--may be present, but, on account of the
general condition of the patient, considerable difficulty is experienced
in endeavouring to demonstrate the existence of this symptom.

[Illustration: FIG. 68. THE CORTICAL MOTOR AND SENSORY AREAS.]

_Incontinence of urine_ has been observed, independent of the condition
of the patient--in other words, without a sufficient degree of coma to
account for the state.

When the tumour is of considerable size, some degree of _paresis_ of the
contralateral side of the body may result, due to backward pressure
exercised by the tumour on the corona radiata preceding from the
pre-Rolandic motor area. Associated with this paresis the deep
_reflexes_ may be increased with extensor plantar reflex (Babinski) and
some diminution of superficial reflexes. The more posterior the tumour
the greater the degree of paresis, and the more exaggerated the
reflexes. When the tumour is situated on the left side the _motor
speech_ centre may be affected.

_Fine tremors_ may be noticed, usually involving the muscles of the
upper extremities, and best demonstrated by asking the patient to hold
his arms horizontally with the palms downwards.

Paresis on the contralateral side may be preceded by or associated with
_fits_, these partaking of the Jacksonian type and accompanied by
conjugate deviation of the eyes towards the side opposite to that on
which the tumour is situated. This association of fits suggests that the
tumour occupies the second frontal convolution.


(_B_) =To the excito-motor frontal region.= In the early stages symptoms
of irritation predominate, the patient suffering from _fits_ of a focal
or Jacksonian type (see p. 189), whilst, later on, _paresis_ of a
progressive type, involving the face or extremities unequally, becomes
evident. In children, however, the rapid transference of impulses from
one motor area to another causes the fits to soon lose their focal
character, _general convulsions_ taking their place.

If the tumour occupies the left side of the brain (in right-handed
individuals) the _motor speech_ centre of Broca may be involved, with
difficulty in or failure of the power of speech.

_Apraxia_ may be present, a condition characterized by inability on the
part of the patient to perform certain familiar purposive movements,
such as sewing, turning a key in the lock, &c.

The contralateral _pupil_ may be contracted from irritation, or dilated
from paralysis; the ipsolateral is variable, more commonly dilated.

In the event of extensive tumour formation and when the growth is
associated with tract degeneration, the deep _reflexes_ will be
increased on the contralateral side, with well-marked extensor plantar
response.


(_C_) =To the post-central, angular, and marginal convolutions.= Attacks
of focal _epilepsy_ are frequently observed when the tumour occupies the
post-central convolution, such developments being probably dependent on
forward pressure effects. These epileptiform attacks, however, are
almost invariably preceded by some _sensory auræ_. Furthermore, the fits
will usually be followed by ‘some degree of anæsthesia or analgesia, a
loss of tactile sensation over half the body, affecting mostly the hand
and foot, with loss of power and astereognosis (inability to recognize
the form and consistency, and to name objects placed in the affected
hand)’ (Beevor).

When situated in the left angular gyrus, _word-blindness_ may
result--inability to appreciate the meaning of written words, &c.

When the tumour presses on the optic radiation, _hemianopia_ results,
with ipsolateral temporal and contralateral nasal blindness.


(_D_) =To the temporo-sphenoidal lobe.= When the tumour occupies the
anterior part of the temporo-sphenoidal lobe, more especially when it is
situated on the internal aspect of that lobe, the degree of _optic
neuritis_ is intense. Perversion or loss of _smell_ may be noticed--a
symptom of difficult determination on account of the general condition
of the patient.

As the result of pressure exercised on the optic tracts
_hemianopia_--with hemianopic pupillary reaction (the pupil not reacting
to light)--may be observed. Pupillary reactions, however, are
complicated by possible paralysis of the third nerve.

Some _weakness of the face muscles_ on the contralateral side is a
fairly constant symptom, presumably dependent on the upward pressure
exercised on the lower motor areas.

A tumour involving the more posterior and central portions of the lobe
may bring about a certain degree of _word-deafness_, whilst objects may
be incorrectly named or named with difficulty, the patient being more or
less aware of his mistakes and evidencing considerable annoyance of the
same.

In whatever part of the lobe the tumour be situated, certain sensory
auræ may be present. Not infrequently the patient falls into the
so-called ‘dream-state’. When sensory auræ are associated with crude
sensations of smell and taste, with chewing or spitting movements, the
tumour is probably situated on the antero-internal aspect of the lobe.


(_E_) =To the occipital lobe.= _Headache_ may be localized to the back
of the head, and _optic neuritis_ is usually both early in onset and
intense in degree. Perhaps the most important localizing symptom is
_homonymous hemianopia_--blindness in the temporal half of the retina on
the same side as the lesion and in the nasal half of the opposite eye.
This is explained by the fact that the fibres of the optic radiation,
passing forwards from the affected occipital region, supply those
retinal areas. The reaction of the pupil will be unaltered, for the
pupillary nerve-fibres, in their course towards the third nerve nucleus,
are only directed backwards as far as the anterior corpora quadrigemina.
Consequently, an interruption of optic fibres between retina and third
nerve nucleus brings about a loss of pupillary reflex when light is
thrown on the blind portion of the retina, whilst if the lesion be
situated further back, pupillary reaction is unaltered. This is
Wernicke’s sign.


(_F_) =To the subtentorial region.= Certain symptoms are more or less
common to all subtentorial tumours, whether they arise within the
cerebellar substance (intra-cerebellar) or immediately outside the
brain-substance (extra-cerebellar). _Headache_ is very severe, and in
about 50 per cent. cases, localized to the back of the head, perhaps
associated with stiffness of the neck muscles and retraction of the
head. _Optic neuritis_ is early in onset and intense in degree. It is
more constant in cerebellar tumour formation than in tumours located in
almost any other part of the brain. The choking of the disk is marked
and hæmorrhages are frequent. _Vomiting_ and other symptoms referable to
increased subtentorial pressure--slow pulse, altered rhythm of
respiration, &c.--are usually well marked.

[Illustration: FIG. 69. THE VISUAL PATHS. O.L., Occipital lobe; O.R.,
Optic radiation; O.T., Optic tracts; P., Pupillary fibres from optic
tract to third nerve nucleus; O.C., Optic chiasma; O.N., Optic nerve; 1,
Blindness of affected eye; 2, Bitemporal hemianopia; 3, Bilateral
homonymous hemianopia, with hemianopic pupillary reaction; 4, Bilateral
homonymous hemianopia, pupillary reaction normal.]

_Vertigo_ is most apparent when the patient is suddenly changed in
position or tries to stand or walk. It appears in two forms, either as a
definite sense of movement of self (subjective vertigo) or of objects
(objective vertigo), or merely as a giddy feeling. In objective vertigo
the sense of displacement of objects is more commonly from the side of
the tumour towards the sound side.

Vertigo is dependent on the influences exercised by the tumour on the
cerebello-vestibular apparatus, and on irritation of those branches of
the fifth nerve which are distributed to the dura mater in the immediate
neighbourhood of the tumour, the impulses being then transferred to the
bulbar nuclei of that nerve and thence to the pneumogastric nucleus.

_Ataxia and inco-ordination of movement_ are also prominent symptoms.
Ataxia results from one or more of the following causes: (1) co-existent
vertigo, (2) asthenia of the muscles of the affected side, the muscular
contractions being irregular in their nature, ill-timed in their action,
and often in excess of actual requirements, and (3) involvement of the
spino-cerebellar tracts and their terminations.

The patient, when standing with the eyes shut and one foot advanced in
front of the other, is unable to maintain his balance, staggers and
tends to fall. No great diagnostic value can be attached to the
direction in which he sways or falls, though, from my own experience, it
would appear more probable that he should lurch towards that side on
which the tumour is situated. In walking, however, there is occasionally
a definite tendency to deviate towards the opposite side, probably due
to over-correction of the weakened muscles on the affected side. The
gait should present the typical appearance of cerebellar ataxia, and the
patient may walk with the head drawn down towards the shoulder of the
affected side, the chin being tilted in the opposite direction.

Inco-ordination of movement is rendered most obvious during active
movement of the limb, decreasing towards the termination of that
movement, and ceasing so soon as the object is attained. This is most
readily demonstrated by the well-known ‘finger-to-nose’ test.

_Nystagmus_ is one of the most frequent symptoms of cerebellar tumour,
usually lateral, the movements coarse or fine, and most marked when the
eyes are directed towards the side of the lesion.

In the more differential diagnosis between _extra- and intra-cerebellar_
tumours, the following points should be noted:--

_Extra-cerebellar_ tumours situated in the cerebello-pontine angle tend
to lead to compression of the eighth nerve (with deafness and tinnitus),
of the seventh nerve (with paralysis of the face muscles), of the fifth
nerve (with anæsthesia of the parts supplied by that nerve), and more
rarely of the sixth nerve (with paralysis of the external rectus). The
ninth, tenth, eleventh, and twelfth nerves are but rarely involved.

_Intra-cerebellar_ tumours seldom give rise to pressure effects on
isolated cranial nerves. On the other hand, one expects ipso-lateral
paresis or paralysis, with exaggerated reflexes (see Fig. 78). Conjugate
deviation of the eyes to the side opposite to that on which the tumour
is placed is a fairly frequent symptom, the deviation being associated
with well-marked lateral nystagmus. When the tumour is of considerable
size, or placed nearer the central portion of the cerebellum, pressure
may be exerted on the pyramidal fibres with paresis or paralysis on the
contra-lateral side of the body.

In addition, allusion should be made to Dana’s symptom--‘cerebellar
fits’--said to be almost pathognomonic of an extra-cerebellar tumour (or
abscess) situated in the cerebello-pontine angle. In such cases, there
may be sudden attacks of tinnitus, vertigo, and apparent loss of
consciousness, during which the patient falls to the ground as if struck
with lightning. The final stage of falling is said to be dependent, not
so much on actual loss of consciousness, as from the absence of
cerebellar innervation and a total loss of equilibrium. These attacks
are brought about by sudden alterations in position.


(_G_) =To the pituitary region.= Considerable research has recently been
carried out, and much knowledge obtained as to the functions of the
pituitary body and the symptoms that result from lesions of the
gland.[44] As is well known, the pituitary body consists of two
portions, an anterior (derived from upgrowth of buccal epiblast) and a
posterior (formed from neural epiblastic downgrowth).

Complete removal of the body in animals invariably terminates fatally,
the patient exhibiting a definite train of symptoms--cachexia
hypophyseopriva--and dying within a few days or weeks, the younger
animals living longer than the older. The symptoms of apituitarism are
as follows: fall of body temperature, lowering of blood-pressure,
increasing feebleness, muscular tremors, a curious attitude resembling
that of defæcation, coma, and death.

On further investigation it was proved that all these symptoms were
observed when the anterior portion of the gland was alone removed,
whilst, on the other hand, extirpation of the posterior half created no
great change in the animal’s general health.

[Illustration: FIG. 70. A PITUITARY TUMOUR.]

In the human being it would appear that the symptoms resulting from the
development of pituitary tumour formation may be classified into two
groups, those of hyper-pituitarism and those of hypo-pituitarism.

In the former case the secretion being superabundant, acromegaly and
giantism are observed. Keith[45] considers that one of the substances
secreted by the gland is of the nature of a hormone, rendering the
osteoblasts hypersensitive to the various stresses that fall upon the
human skeleton during life, and that the osteoblasts, at the origins and
insertions of muscles, become increasingly sensitive to the traction of
muscles. Muscular impressions and processes of the skeleton become
exaggerated by the new bony matter, and if the epiphyseal lines be
still open, the osteoblasts of which appear to be specially affected,
giantism is produced. The skull and skeleton of the giant O’Brien are
regarded as typical examples of the results due to over-secretion of the
gland.

Hypo-pituitarism leads to a striking and rapid development of fat
(adiposity), loss of sexual power and amenorrhœa, persistence of sexual
infantilism (if the patient be attacked when young), harsh skin and
œdematous tissues, subnormal temperature, and psychic disturbances.

In any case, whether the secretion of the gland be increased or
decreased, the developing tumour tends to compress those cranial nerves
with which it is in close anatomical relation. For instance, the gland,
being situated immediately behind the optic chiasma, tends to compress
the mesial nasal optic fibres producing bilateral temporal hemianopia,
with primary optic atrophy as a final result. In some cases optic
neuritis is observed with secondary atrophy. The third, fourth, and
sixth nerves may also be affected, with consequent squints, ptosis, and
perhaps complete ophthalmoplegia.

In addition, it should be noted that glycosuria and albuminuria have
been observed.

       *       *       *       *       *

In the _general diagnosis_ of brain tumours, reference must be made to
_Lumbar puncture_ and _X-ray investigation_.


=Lumbar puncture.= With respect to the desirability of carrying out
lumbar puncture in brain tumours and the value of the information
obtained, considerable difference of opinion exists. Lumbar puncture
supplies information as to the tension of cerebro-spinal fluid and as to
its bacteriological and cytological character. The evidence so obtained
as to tension is of little value in view of the proved increase of
intracranial pressure as evidenced by the mental condition of the
patient, the headache, optic neuritis, &c. On the other hand,
bacteriological and cytological examination of the fluid may point to
the tuberculous or syphilitic composition of the tumour, thus offering
help from the point of view of treatment. Still, information of almost
equal importance can be obtained by tuberculin, Wassermann, and other
tests. There is also considerable risk attendant on the process. The
rapid withdrawal of cerebro-spinal fluid has been followed by
disastrous results, the medullary stem being suddenly forced downwards
into the foramen magnum, with corking up of that aperture, and complete
upset of the medullary centres. Such a disaster is the more likely to
occur when the tumour is subtentorial in position. Looking at the
question from the broadest point of view, it would appear that the
performance of lumbar puncture in cases of suspected brain tumour is
fraught with considerable peril.


=X-ray examination.= X-ray examination should always be carried out.
More commonly the results are negative, the nature of the tumour seldom
permitting sufficient shadow formation. Occasionally the firmer and
denser tumours allow of a more definite result. When the tumour arises
from the bone, or is so situated as to change the shape of the part with
which it is in contact, valuable information will be obtained. For
example, the hollowing out and general enlargement of the sella turcica
in pituitary tumour formation.


=Treatment.=


_Indications for operation._ The indications for operation must be
considered under two groups:--

Those for radical operation aiming at the removal of the tumour.

Those for palliative operation aiming at the alleviation of symptoms.


_For the radical operation._ According to Risien Russell,[46] the
following are the main indications:--

(1) Cases in which the tumour can be accurately diagnosed.

(2) Cases in which the tumour is situated in an accessible position. The
more favourable sites are the surface of the cerebrum, the lateral lobe
of the cerebellum, and the cerebello-pontine angle.

(3) Cases in which there is reason to believe that the tumour is simple,
and of such a nature that it can be removed from its bed.

(4) Cases in which there is reason to believe that the removal of the
tumour will not greatly imperil the patient’s life, and, furthermore,
will not result secondarily in the development of fits, paralysis,
aphasia, &c.


_For the palliative operation._ The following are the main indications
for operation:--

To prolong life.

To alleviate the severe and persistent headache.

To stop fits.

To save the sight.

And, in general, to benefit the patient by reducing the increased
intracranial pressure, _even though it may be quite impossible to remove
or even locate the tumour_.

Of all the considerations enumerated above, for which palliative
measures are indicated, there is no symptom which more urgently demands
alleviation than optic neuritis. This question of sight-saving may be
accepted as a basis on which to estimate the value of palliative
measures in general. It is obvious that no mere ‘decompression’
operation will save the sight when the optic inflammation has progressed
to atrophy, and even in the earlier conditions of neuritis cases must be
carefully chosen. Herbert Bruce[47] admirably clinches the matter in the
following words: ‘As to the prediction of improvement of vision after
trephining, everything depends on the condition of the disks. Yellowish
white patches of exudate or white atrophic changes, especially when
associated with macular changes, all indicate that the secondary changes
in the disks will be permanent. In proportion to this development will
the vision be impaired, whilst when the loss of vision has been
dependent on the swelling of the disks, then not only will the sight be
saved but largely improved. In other words, one might say, therefore,
that when the neuritis has not progressed on to atrophy the sight would
be saved.’ Even in the event, however, of the ocular conditions being
unfavourable for palliative operation, other factors in the case still
remain--the terrible and persistent headache, the fits, the emaciation
from vomiting, &c., all of which require the most careful consideration,
and all of which can be remedied by an efficient decompression
operation.


=Radical operation for cerebral tumours.= After the usual preparatory
treatment and the application of the scalp-tourniquet, the skull is
opened either by craniectomy or craniotomy. The two methods--with their
relative advantages and disadvantages--have already been described (see
Chapter II), but there can be no question that a brain tumour should be
exposed by the formation of an osteoplastic flap. Such a procedure is
called for on the ground that the exact localization of the tumour is
always a matter of very great difficulty, and that it is impossible to
foretell with certainty as to whether it will be feasible to remove the
tumour or not.

[Illustration: FIG. 71A. FIRST STAGE IN THE FORMATION OF AN OSTEOPLASTIC
FLAP. Gigli’s saw, protected from the dura mater by the special
director, passing between the two trephine holes. For further
description, see text.]

[Illustration: FIG. 71B. SECOND STAGE IN THE FORMATION OF AN
OSTEOPLASTIC FLAP. The bone-flap turned down and the dura mater
exposed.]

[Illustration: FIG. 71C. THIRD STAGE IN THE FORMATION OF AN OSTEOPLASTIC
FLAP. The dural flap turned down and the brain exposed. Note the
relation of the scalp, bone, and dural incisions to one another.]

A bone-flap is framed suited to the occasion, and permitting adequate
exposure of the dura. The question then arises as to whether the dura
should be incised, the brain explored, and an attempt made at the
removal of the tumour, or whether these procedures should be postponed
till the patient shall have recovered from any shock attendant on the
first stage. The two-stage operation--first advocated by Horsley--is
insisted on by some surgeons. By others it is maintained that it is
preferable to complete the operation at one sitting, mainly on the
ground that two anæsthetics and two operations are more dangerous than
one. As to which course should be adopted is entirely dependent on the
general condition of the patient at the termination of the bone-flap
formation. If his condition is quite satisfactory, if there has been but
little hæmorrhage, and if the blood-pressure shows no tendency to drop,
then it is perfectly justifiable to ‘carry on’, opening the dura mater
and searching for the tumour. Still, as the shock entailed during the
first stage may be considerable, as the surgeon cannot possibly foresee
with certainty what lies beneath the dura mater, and as considerable
time must elapse, and some hæmorrhage result during the further
procedures required for the reflection of the dura mater and removal of
the tumour, it follows that it is generally advisable to conduct the
operation in two stages, the second operation being carried out some
days later. Not less than five to seven days should elapse between stage
one and stage two, the scalp-flap is then but lightly healed, whilst all
blood-vessels should be sealed. The patient also will have entirely
recovered from any shock attendant on the first stage.

At the second stage, the dura may be more or less covered with a film of
coagulated blood, meningeal arteries and the outline of venous sinuses
being correspondingly obscured. Consequently, if the dural flap proposed
for the second operation should include these structures, the meningeal
vessels may be ligatured and the sinuses mapped out with guide-threads
at the completion of the first stage.


_Examination of the dura mater._ Considerable help may be obtained by
examination of the dura mater, both with regard to the localization of
the tumour and investigation as to its nature. Pulsation may be
abolished or diminished, whilst the tenseness of the membrane is
increased in direct proportion to the size and site of the tumour. The
membrane also may be œdematous or adherent, anæmic in colour from
pressure exercised by an underlying tumour, reddened from
vascularization, grey-brown from the immediate presence of a malignant
mass, plum-coloured from the adjacency of a subdural hæmorrhage, opaque
from the presence of an arachnoid cyst.

Some evidence as to the nature of the tumour may be obtained by
palpation--fluctuation suggesting cyst formation, solidity pointing to
more definite formation.


_Opening the dura mater._ The membrane can be opened either by crucial
incision or by flap formation. The latter method is to be preferred. All
meningeal vessels that cross the line proposed for dural section must be
underrun on either side of that line. The dural incision should always
fall short of the margins of the gap in the skull by at least ¹⁄₂ inch,
in order to allow of accurate approximation at the termination of the
operation.

The following points with respect to the opening of the dura mater,
though already enumerated in Chapter II, should be noted. The membrane
is lightly incised with the scalpel, and, so soon as the pia-arachnoid
is exposed, the section completed with the blunt-pointed scissors, or on
a grooved director. The dural flap is then turned down and the brain
laid bare. It is most essential that every precaution should be taken to
avoid injury to superficial cerebral veins--the cortex is probably under
high tension, firmly compressed against the dura mater and bulging out
forcibly so soon as tension is relieved.


_Examination of the brain._ In the event of the exposure of the tumour,
its removal can at once be attempted. If, however, the tumour be
subcortical in position, its position and boundaries may be estimated by
electrical stimulation, palpation and exploration.

_Electrical stimulation_ will evidence whether the area exposed
corresponds to the symptoms evinced by the patient. With respect to the
actual technique, one pole is placed on the patient’s extremity--it
matters not which, though preferably on the homo-lateral side--the other
over the exposed brain. The current should be just strong enough to
contract exposed muscle--some of the fibres of the temporal muscle are
generally available for the purpose. If there is much pia-arachnoid
œdema, some of the fluid should be evacuated--by gentle scratching of
the membranes--and the bare brain stimulated. In the event of complete
degeneration of the pyramidal tracts there is little or no response to
such stimulation. Under other circumstances the results are quite
definite.

_Palpation_ may reveal the nature of the tumour, whether fluid or solid.

_Exploration of the brain_ should only be undertaken in the light of a
reasonably certain diagnosis, and every precaution must be taken to
avoid needless damage to the cerebral substance. The exploration should
invariably be preceded by incision with the brain-knife or scalpel,
introduced in such a manner as to avoid injury to all visible vessels
and directed at right angles to the surface of the brain, so as to cause
the least possible damage to the corona radiata, &c.


_Extirpation of the tumour._ The proportion of brain tumours surgically
removable is small, and even when the tumour is fully exposed
considerable experience is required in estimating the possibility of
removal.

When the tumour is circumscribed, whether meningeal, cortical, or
subcortical, it may be shelled out of its bed with greater or lesser
ease according to its nature and position. This shelling out process is
carried out with an ordinary tea-spoon or scoop. Hæmorrhage may be
severe though generally readily controlled by lightly packing with dry
gauze. More rarely one or more of the superficial vessels will require
to be underrun with a small needle threaded with the finest catgut.
Muscle grafts (see p. 18) may be of considerable assistance.

If a cyst be found it may be possible to shell it out entire, failing
which the parietal wall is freely dissected away, and the cavity drained
for two or three days.

[Illustration: FIG. 72. COMBINED FLAP FORMATION AND DECOMPRESSION. After
osteoplastic resection, the tumour has been found irremovable. The dura
mater is therefore sewn back in position, after which a portion of the
bone is nibbled away from the bone-flap--as depicted in the
illustration--and the underlying dura mater freely incised.]

If the tumour be extensive and ill-defined in margin, no attempt should
be made at removal, the surgeon remaining content with the second
desideratum of brain tumours in general--the production of a general
decrease of intracranial pressure. This might be readily effected by
leaving the dura open and by removing at the same time the osseous
portion of the osteoplastic flap. The bone is readily dissected away and
free decompression would be permitted. In such cases, however, the
hernial protrusion is usually excessive, and insomuch as an osteoplastic
flap is more often than not framed over the Rolandic region, the
protrusion would include the motor area with disastrous results on the
contra-lateral extremities. This course, therefore, should never be
adopted. In such cases it is infinitely preferable to follow Cushing’s
method of combined exploration and decompression. This is done as
follows: ‘From under the portion of temporal muscle which has been
turned back with the flap, a roughly semicircular area of bone is cut
away with heavy rongeurs, which remove bone without jar, and so without
risk of stripping the remainder of the resected bone from the soft
parts. This accomplished, a similar area is rongeured away from the side
of the skull well down the temporal fossa under the tourniquet, the
temporal muscle being held away by a retractor. If the base of the bone
has been made sufficiently broad, a margin possibly a centimetre in
width can be left on each side as a support for the flap after its
replacement. A subtemporal bone defect is thus secured with even less
difficulty than is experienced in making the usual subtemporal opening
from without through a split muscle incision. The dura is then carefully
opened and incised in a stellate fashion to the margin of what promises
to be a sufficient circle of denuded cortex for a generous
decompression.’


_Closure of the dura and reposition of the flap._ Whether the tumour has
been exposed and removed, is deemed irremovable, or has not been found,
the dural flap should be approximated and carefully sutured in position.
In many cases, however, this dural approximation is exceedingly
difficult to accomplish, by reason of the outward bulging of the
diseased or œdematous brain. This difficulty may be overcome by adopting
one or more of the following methods:--

_Elevation of the head_, thus reducing the amount of blood in the brain.

_Lumbar puncture_, a method that presents some danger when the surgeon
has to deal with a subtentorial tumour, but which bears in its train
excellent results from the point of view of reduction of intracranial
pressure. The danger arises from the fact that the sudden escape of
cerebro-spinal fluid may cause the brain-stem to be engaged in the
foramen magnum, with disastrous results on the medullary centres.

_Ventricular puncture_, when the ventricles are dilated. A blunt-pointed
aspirating needle is introduced into the lateral ventricle through the
most prominent portion of the exposed brain, and a sufficient quantity
of cerebro-spinal fluid evacuated.

_‘Milking’ the pia-arachnoid_, the pia-arachnoid being pricked with a
needle in several places and the contained fluid squeezed out.

_Subtemporal decompression_--the final resource. When all other measures
fail, a subtemporal decompression may be conducted on the opposite side
of the brain.

The dura should be accurately sutured with numerous interrupted silk
sutures. It is very important that every precaution should be taken to
prevent the continued escape of cerebro-spinal fluid, and, for this and
other obvious reasons, it is necessary to avoid drainage whenever
possible. If such a course should be necessary--by reason of
hæmorrhage--a cigarette drain may be brought out at the most dependent
and convenient angle of the dural flap, and through one of the trephine
holes or gap purposely cut in the bone-flap.

In any case, the bone-flap is replaced, resting on its shelf and
anchored by means of numerous deep sutures, each of which picks up the
aponeurosis or muscle both along the upper border of the flap and the
two downward vertical prolongations. These sutures will also control
bleeding from the divided scalp-vessels. The tourniquet is removed,
dressings applied, and the whole maintained firmly in position by a
gauze bandage applied circumferentially. These dressings are supported
by bandages and the patient sent back to bed.

If the tumour has been exposed by _craniectomy_, the gap in the skull
will probably require protection. This procedure (see Chapter VI) can be
carried out at the termination of the main operation or at a later date.
This latter course is to be preferred.


=Radical operation for cerebellar tumours.= Craniectomy may be regarded
as the operation of choice in the exposure and removal of cerebellar
tumours. The formation of an osteoplastic flap is contra-indicated (see
p. 29). The operative procedures vary according as to whether it is
desired to expose the one or both cerebellar hemispheres. Bilateral
exposure, though presenting the great advantage of offering a larger
field for exploration, is by far the more serious of the two operations.


_Unilateral cerebellar exposure._ The patient being placed in the
semi-prone or face-down position, the incision starts at the posterior
border of the apex of the mastoid process, curves inwards along the
superior curved line of the occipital bone to the occipital
protuberance, and then passes straight down the middle line of the neck
for 2 to 3 inches. If the incision is deepened at once to the bone,
hæmorrhage is severe. The incision should first involve the skin and
then the muscles attached to the occipital bone. Each vessel as
encountered is clipped and tied. The flap must be turned down right up
to the posterior margin of the foramen magnum.

The flap being held aside, the pin of the trephine is placed in such a
manner that the disk to be removed will correspond to the thin central
portion of the cerebellar fossa. The trephine, placed low down, is
directed more or less towards the anterior fontanelle.

The disk being removed, the bone is freely cut away with rongeur
forceps--outwards to the posterior border of the mastoid process,
upwards to the curved line, inwards to near the middle line, and
downwards to the posterior margin of the foramen magnum.

This generally completes the first stage of the operation, for, in
cerebellar tumours, it is usually advisable to complete the operation in
two stages. The scalp-flap is replaced, lightly sewn into position, and
the patient sent back to bed.

A few days later the flap is again turned down, the dura incised, and
turned down as a flap the convexity of which corresponds to but falls
short of the line of the lateral sinus. The cerebellar substance is then
examined and the tumour removed after the lines enumerated in dealing
with cerebral tumours. Greater difficulty, however, is experienced in
the attempted removal of cerebellar tumours, for the operator is working
in a very confined space, and because the cerebellum tends to herniate
through the adventitious hole in dura and bone. Two other factors must
be taken into consideration: (1) the danger incident to all cerebellar
operations of respiratory failure,[48] and (2) the friability of the
cerebellar substance. Every care must be taken to avoid unnecessary
damage of the brain-matter.

When the tumour is situated in the cerebello-pontine angle, a somewhat
favourite site for tumour formation, ‘lateral displacement’ of the
cerebellum towards the middle line will aid considerably in the
exposure. A flat retractor, bent to a suitable curve, is introduced
between the dura and the cerebellum, and the brain-matter gently but
firmly retracted towards the middle line. As the brain yields to the
pressure the tip of the retractor is insinuated towards the posterior
surface of the petrous bone. With the aid of a head-lamp a good view may
usually be obtained of the region involved, and, as the tumour is but
lightly attached, its removal can be undertaken.

The dura is then carefully sutured and the scalp-flap accurately
replaced, deep sutures for the muscles and a few surface sutures for the
skin. Drainage should be avoided whenever possible--the discharge of
cerebro-spinal fluid is fraught with considerable danger. The gap in the
skull requires no other protection than that afforded by the mass of
neck muscles.

[Illustration: FIG. 73A. UNILATERAL EXPOSURE OF THE LEFT HALF OF THE
CEREBELLUM BY CRANIECTOMY. The scalp-flap has been turned down and is
fully retracted. The cerebellum has been exposed by means of a
crescentic dural flap.]

[Illustration: FIG. 73B. BILATERAL EXPOSURE OF THE CEREBELLUM BY
CRANIECTOMY. The left half of the cerebellum has been exposed. The
trephine is being applied over the right cerebellar region. Note the
position of the trephine and the direction in which it is being
applied.]

[Illustration: FIG. 73C. BILATERAL EXPOSURE OF THE CEREBELLUM BY
CRANIECTOMY. The walls of both cerebellar fossæ have been cut away,
exposing the bulging dura mater. The Gigli saw is in position for
removal of the bridge of bone intervening between the two cerebellar
fossæ.]

[Illustration: FIG. 73D. BILATERAL EXPOSURE OF THE CEREBELLUM BY
CRANIECTOMY. The bridge of bone has been removed, two crescentic flaps
of dura mater have been turned down, and the falx cerebelli has been
ligatured in two places and divided.]


_Bilateral cerebellar exposure._ This operation is also done in two
stages. In the first, each cerebellar fossa is exposed in turn, the
scalp-flap being framed and the trephining and cutting away of the bone
carried out in the manner previously described for unilateral exposure.
The osseous bridge which separates the two openings in the skull is
divided above and below with Gigli’s saw, and the intermediate part
removed. This completes stage one.

In the second stage, again carried out a few days later, two dural flaps
are turned down, each similar to the one described in unilateral
exposure. This leaves a central portion of dura, that part which
encloses the occipital sinus and to which the falx cerebelli is
attached. By means of an aneurysm needle, threaded with catgut, passed
through or around the falx, the occipital sinus is ligatured above and
below, the ligatures being applied as high and as low as circumstances
permit. The falx is then divided between the two ligatures and the two
flaps thrown upwards and downwards respectively.

The extra space so afforded not only allows of the exposure of both
hemispheres, but also permits of the further dislocation of the one lobe
towards the opposite side, thus facilitating the examination of the
lateral aspect of the cerebellum and of the cerebello-pontine angle.

This bilateral method is a serious operation. Hæmorrhage may be severe,
and the attendant risks of respiratory failure are not inconsiderable.
It should only be adopted (1) when a tumour is so situated or so
extensive that more space is required than supplied by unilateral
exposure, and (2) when bilateral cerebello-pontine tumours are
suspected.


=Palliative operations for cerebral and cerebellar tumours.= A primary
palliative operation may be conducted over the region of the tumour
itself, in the cerebellar region, or over the temporal lobe--one of the
so-called ‘silent’ areas of the brain.

It is obvious that the greatest degree of pressure relief will be
obtained by craniectomy conducted over the region of the tumour itself.
To this course, however, there are two great objections: (1) the exposed
cortex most commonly includes the motor area, herniation of which will
lead to disastrous effects on the extremities of the contra-lateral
side--spasticity, paralysis, aphasia, &c.; and (2) the herniation of
brain-matter including, or closely related to, an irremovable tumour
tends to lead to œdema of the brain tissues and softening of and
hæmorrhage into the growth, with subsequent rapid development of the
outwardly protruded mass.

With respect to cerebellar decompression operations, I must confess that
I have formed a most unfavourable opinion. The subtentorial pressure can
undoubtedly be relieved most effectually by such methods, but the
immediate results are not infrequently disastrous, the patient dying
within a few days as a result of the complete upset of medullary
centres.

In the event of the surgeon deciding to confine his attempts to
palliative treatment--alleviation of symptoms only--the _subtemporal
operation_ of Cushing is certainly the method of choice. The technique
of the operation and its general advantages have already been discussed.
It merely remains to add that, when the operation is conducted for
tumour relief and not for injury as discussed in Chapter IV, no attempt
is made to explore the temporo-sphenoidal lobe and drainage is
contra-indicated. The dura, widely incised, is left open, the temporal
muscle and fascia accurately sutured, and the scalp-flap secured with
fine silk sutures.

With regard to the side on which this subtemporal decompression
operation is to be conducted, the best results are obtained by operating
on that side on which the tumour is situated. In the event of doubt, the
right side is chosen, so avoiding any possibility of including, in the
hernial protrusion, the motor speech area of Broca. The cranial defect
should be made as large as possible, and in the event of failure in
bringing about adequate decompression, a similar operation is conducted
at a later date on the opposite side of the skull.

After subtemporal decompression there should be no mortality.

The immediate results are eminently satisfactory--headache is relieved,
optic neuritis steadily diminishes, vomiting ceases, and the general
condition of the patient is immensely improved.

The expectancy of life after such decompression operations requires
careful consideration. So much depends on the nature of the tumour that
it is difficult to make more than a general observation. In many cases
life has been prolonged for one to two years, whilst instances are
recorded in which the patient has lived for five to six years--not in a
miserable condition as might be imagined, but in comparative comfort.

It might be added that, as the tumour grows, a one-sided subtemporal
decompression may gradually become insufficient. In such cases,
recrudescence of symptoms--redevelopment of optic neuritis, &c.--may be
met by further decompression on the opposite side of the head.


=Operations for tumours of the pituitary body.= The pituitary body may
be approached by the frontal, temporal, and nasal routes. The _temporal
route_, advocated by Caton and Paul[49] and Horsley, possesses the
disadvantage that the surgeon, whilst utilizing an approach similar to
that used in the Hartley-Krause operation for trigeminal neuralgia,
encounters on his way the structures laterally situated to the pituitary
body, the internal carotid, the cavernous sinus, the third, fourth, and
sixth nerves, and the ophthalmic division of the fifth. The anatomical
difficulties are therefore considerable. Added to this, the tumour, in
its hollowing out of the central portion of the sella turcica, may leave
such lateral osseous walls that an approach from the side is impossible.

The _frontal route_ is strongly advocated by Krause.[50] He states that,
‘an osteoplastic flap is framed in the frontal region, immediately to
one side of the middle line, so as to avoid the superior longitudinal
sinus and frontal air sinus, and turned upwards. It is essential that
the operator should approach the tumour along the floor of the anterior
fossa, and, for this purpose, it may be deemed necessary to chip away
the bone in the region of the supra-orbital ridge. Some days later, the
final stages of the operation are conducted. The dura mater covering
the frontal lobe is stripped away from the bone and traction applied to
the dura by means of broad flat spatulæ. When the lesser wing of the
sphenoid is exposed, the dura mater is opened in the vertical direction
on a line with the lower median angle of the wound at a depth of 5 to
5¹⁄₂ centimetres, as measured from the anterior surface of the frontal
bone. If the incision is made at a deeper point there is danger of
injury to the optic nerve, which is covered with dura mater in this
situation. Laterally the dura is opened parallel to the posterior border
of the lesser wing of the sphenoid, about ¹⁄₂ cm. in front of it, to
avoid the sinus which lies immediately in contact with the edge of the
bone. This exposes the optic nerve, coming from the chiasma and the
internal carotid. The pituitary body is located beneath the anterior
edge of the chiasma. The diaphragm of the sella turcica is now carefully
incised with a small hook-shaped scalpel, and the hypophysis is readily
removed.’

The _nasal route_, advocated by Bruns and successfully carried out by
Schloffer[51] and Cushing, seems to offer the greatest advantages and
give the most successful results. The general details of the operation
are as follows: starting either beneath the upper lip or externally at
the base of the septum, the mucous membrane is peeled away from each
side of the vomer, and, by gradual piecemeal removal of that bone, the
advance is carried out towards the base of the skull in what may be
called an intra-mucous space. By the introduction of suitable
instruments into this space the cavity is gradually enlarged, at the
expense of the turbinated bones which are compressed by the dilating
instruments. By this means--gradual removal of the septum--the operator
approaches the base of the skull, always working between the two layers
of mucous membrane, and always avoiding, with the greatest care, any
laceration of the same. Laceration at once converts the more or less
aseptic operation into an infected one. When the base of the skull is
laid bare in the region of the sphenoidal sinus, the bone is there
chiselled away and the under surface of the pituitary body exposed. It
can then be removed piecemeal.

The general details of the operation as enumerated above may require
amendment as our knowledge increases. Sufficient has been said,
however, to point out the various methods of approach and the advantages
claimed for the nasal route.


=Results of operation on brain tumours.= Statistics are always
fallacious, and this is especially the case with regard to operations on
tumours of the brain. Few surgeons have operated on a sufficient number
of cases to compile satisfactory statistical tables. These tables are
generally made up from the combined experience of many operators, all
using their own methods. The following, however, will serve to give an
approximate idea as to mortality, &c.


_Mortality._ From earlier records the immediate mortality was estimated
at 30-40 per cent. Duret, however, records 400 cases with a mortality of
19·5 per cent., 58 cases dying from shock, 10 from hyperpyrexia, and 10
from hæmorrhage. In my own practice, the mortality may be estimated at a
much lower figure. Perhaps I may be too conservative, but I hold the
view that, unless the tumour is readily exposed and equally readily
removable, it is inadvisable to carry out further measures for its
eradication. Moreover, the general technique of brain surgery has
advanced with rapid strides, and the question of early and accurate
localization has received equal attention. The mortality has diminished
proportionately, and may be estimated at less than 20 per cent. So much
depends on the surgeon and on the nature of the tumour, its position and
localization, that it is impossible to make any absolute statement as to
the risk to life attendant on operation. If all tumours were fibromata,
cortically situated, and accurately diagnosed, the operation, in the
hands of a skilled neurological surgeon, should present but a very low
mortality. So long, however, as surgeons will persist in burrowing into
the brain substance for a supposed subcortical tumour, so long will the
mortality remain high. The great secret in operating on a brain tumour
lies in knowing when to terminate the attempt at removal of the tumour
and when to rest content with a pure ‘decompression’.

It is obvious, therefore, that cortical tumours--more especially such as
give rise to early localizing symptoms, e.g. Rolandic tumours--offer a
better prognosis than when the surgeon has to deal with subcortical,
central, and basal tumour formation.


_The mortality according to the region affected._ The following table,
from a series collected by Knapp, supplies valuable information as to
the regional mortality.

  Frontal tumours  32 cases       Mortality, 25 per cent.
  Central    „    231   „            „       23     „
  Parietal   „     29   „            „       41     „
  Temporal   „     17   „            „       29     „
  Occipital  „     10   „            „       20     „
  Cerebellar „     54   „            „       45     „

Sir Victor Horsley draws attention to this question in the following
manner: ‘If a line be drawn from the frontal eminences to the occipital
protuberance, it is obvious that more shock results from operations
below that line than from above, and as we proceed from the frontal to
the cerebellar pole of the encephalon.’


_The mortality according as to whether the tumour is found or not._
According to Horsley, of 79 cases in which a correct diagnosis was made
and the tumour removed, 7 died from shock; whilst in 16 cases
inaccurately diagnosed, 6 died--a mortality of 9 per cent. in the first
case as against 37 per cent. in the second.

The added danger resulting from unsuccessful attempts at finding the
tumour must not be advanced as an argument against the palliative
operations, for the failure to find and remove the tumour implies
diligent search for the neoplasm, with necessary prolongation of
operative procedures, and perhaps extensive manipulation of the brain
substance. Statistics and experience both afford conclusive evidence
that accurate localization is essential for the success of the
operation.

[39] Paton, _Brain_, vol. xxxiii, p. 67.

[40] _Pyschische Störungen bei Hirntumor_, 1903.

[41] _Lettsomian Lectures_, by the late Dr. Charles Beevor; Duret,
_Tumours of the Brain_; Nothnagel, _Tumours of the Brain_, &c.

[42] _Brit. Med. Journal_, March 1, 1908.

[43] _Lancet_, July 10, 1909.

[44] Crowe, Cushing, and Homans, _Johns Hopkins Bulletin_, May 1910.

[45] _Lancet_, April 15, 1904.

[46] _Brit. Med. Journal_, October 26, 1906.

[47] _Annals of Surgery_, 1907, p. 543.

[48] In the event of cessation of respiration during trephining, the
skull should be opened and the dura incised with the utmost expedition.
The relief of tension so afforded often allows of respiratory
recovery--with or without artificial respiration.

[49] _Brit. Med. Journ._, 1893, p. 1421.

[50] _Surgery of the Brain_, vol. i, p. 117.

[51] _Wien. klin. Wochensch._, No. 21, 1907.




CHAPTER VIII

THE INFECTIVE DISEASES OF THE BRAIN AND MENINGES: ABSCESS OF THE BRAIN,
MENINGITIS, LATERAL AND CAVERNOUS SINUS THROMBOSIS, HERNIA CEREBRI


ABSCESS OF THE BRAIN

Abscess of the brain may be considered under the following headings:--

Multiple abscess.

Acute traumatic abscess.

Chronic abscess.


=Multiple abscess.= Multiple abscess results from the lodgement of
infected emboli which, derived from an acute infective osteomyelitis,
endocarditis, gangrene of the lung, &c., are carried by the blood-stream
to the brain. Multiple abscess of the brain may therefore be considered
as part of a general infection. On account of the symptoms dependent on
the primary infection and on the secondary pyæmic developments, a
diagnosis can seldom be determined, and, even in those rather
hypothetical cases in which suspicion may be aroused, surgical
interference is quite useless and the prognosis hopeless. It is,
therefore, quite unnecessary to discuss the matter further.


=Acute traumatic abscess.= Acute traumatic abscess of the brain most
commonly arises in connexion with an infected compound fracture of the
skull. In the event of laceration of the dura mater, infective organisms
have a ready means of access both to the meninges and to the brain
itself, meningitis or cerebritis resulting. This liability to meningeal
and brain infection is increased when hair, portions of clothing,
bullets, or other foreign bodies are embedded amongst the comminuted
fragments of bone, or driven into the brain substance. In the event of
the dura mater remaining intact, meningitis or cerebritis may still
develop if, as the result of scalp suppuration, the diploic vessels
become thrombosed and plugged with bacteria, some of which may be
carried inwards by the reversed blood-stream, and perhaps by lymphatic
connexions.

The infection may remain localized to the adjacent brain substance, an
acute traumatic cerebral abscess resulting, or may become more widely
diffused--diffuse cerebritis--a condition usually associated with
general meningeal infection.

An acute traumatic cerebral abscess is almost necessarily situated
immediately beneath the site of osseous and membranous lesion, being, in
fact, more a meningo-cortical abscess than a brain abscess proper. The
boundaries are but ill-defined, the walls ragged, and the contents of a
brown-red colour. The surrounding brain is in a condition of red
softening, that is to say, extensively infiltrated with leucocytes, the
vessels thrombosed and teeming with bacteria, whilst minute
extravasations of blood lead to the characteristic colour both of the
contents of the abscess and of the surrounding tissue.

In the more chronic cases, the surrounding area shows some attempt at
repair, dense armies of leucocytes barring the way to the spread of the
infection, and, in the more favourable cases, allowing of the formation
of a definite fibrous barrier.


=Symptomatology.= The symptoms resulting from an acute traumatic
cerebral abscess are largely dependent on the site of the abscess. In
the earlier stages of development suspicion may be aroused by the
presence of persistent headache--frequently localized to the region
primarily affected--by mental and bodily irritability, restlessness, and
pyrexia. All these symptoms may, however, be produced by the unhealthy
condition of the scalp-wound--free suppuration, bare bone, and
extra-dural suppuration.

On or about the third day, the condition of the patient becomes more
grave, the change for the worse being usually of rapid development, and
preceded by severe rigors and general convulsions. The patient shows
further signs of mental irritation, being delirious, restless, and
occasionally actually maniacal.

The temperature is high and rigors are frequent. The pulse is small and
rapid, the respiration increased in frequency, irregular, and often
partaking of the Cheyne-Stokes type. The face is livid, the skin hot and
burning. Vaso-motor disturbance is evidenced by profuse sweating and
well-marked _tache cérébrale_.


=Prognosis and treatment.= The prognosis is almost hopeless unless
radical measures are adopted in the early stages. The scalp-wound should
be enlarged and comminuted fragments of bone removed, or the skull
trephined over the region of the suspected abscess. The lacerated dura
mater is freely opened up and the surface of the brain exposed. Purulent
material is gently removed, and the wound closed in such a manner as to
allow of free drainage.

Even under the most favourable local conditions the prognosis is bad.


=Chronic abscess.= As a preliminary statement it must be pointed out
that breaking down new growths, softening gummata, caseating tuberculous
masses, actinomycotic and hydatid cysts, are regarded in the light of
tumour formation and are discussed elsewhere.

Of 52 cases of brain abscess admitted of recent years into St.
Bartholomew’s Hospital, 41 partook of the chronic type, 30 being
dependent on otitic disease, 3 on frontal sinus suppuration, 5 resulting
from lung disease, and 2 of uncertain origin. The 11 acute cases were
either traumatic or pyæmic.

From these and other statistics it may be regarded as generally accepted
that the majority of brain abscesses are secondary to chronic disease of
neighbouring bone, and more especially middle ear disease. This being
the case, it might naturally be inferred--on anatomical grounds--that
the temporo-sphenoidal lobe of the cerebrum and the cerebellum are more
liable to infection than any other part of the brain. From 100 cases
treated at my hospital the temporo-sphenoidal lobe and cerebellum were
involved in the proportion of about 2 to 1. Körner,[52] reporting on
another 100 cases, gives the following data:--

  Abscess of the cerebrum        62 cases
    „         „  cerebellum      32   „
    „ in both situations          6   „

Hunter Tod,[53] reporting on 100 cases treated at the London Hospital,
found that in children under 10 years of age temporo-sphenoidal abscess
occurred in 87 per cent. cases, and cerebellar in 13 per cent., whereas
in adults cerebral abscess occurred in 65 per cent. and cerebellar in
35 per cent. The development of temporo-sphenoidal and cerebellar
abscesses in the same case was observed in 5 per cent. cases.


=Pathology.= Insomuch as chronic middle ear disease forms the main
predisposing factor in the development of abscess of the brain, the
pathology of brain abscess in general may be considered by discussing
the main features peculiar to otitic abscess in particular.

As the result of chronic middle ear disease, the mucous lining of the
middle ear and its accessory cavities becomes destroyed, the antrum
filled with cholesteatomata, and the middle and external ears with
granulations. The discharge of pus, previously free, is obstructed,
partial or complete blockage occurring. The destruction of the mucous
lining allows of invasion of the surrounding bone, the veins become
thrombosed and filled with bacteria, and the cancellous spaces blocked
with granulations. Further erosion of the bone results, both in the
upward direction towards the tegmen tympani and in the backward towards
the lateral sinus groove and cerebellum. The veins of the tegmen
communicate freely with those of the temporo-sphenoidal lobe, whilst
those ramifying in the mastoid region either communicate with the
lateral sinus itself or with the anterior cerebellar venous system.
Infection may therefore spread (1) _upwards_ to the temporo-sphenoidal
lobe, or (2) _backwards_ to the lateral sinus and cerebellum. In the
former case, meningitis or temporo-sphenoidal abscess develops: in the
latter instance, meningitis, lateral sinus thrombosis, or cerebellar
abscess.

For the formation of a brain abscess it is, of course, essential that
the brain membranes overlying the main site of osseous erosion should be
sealed off in such a manner as to prevent a general infection of the
meningeal region, the dura becoming adherent to the eroded tegmen, &c.
It is œdematous and throws out granulations, both on its parietal and
visceral aspects. The parietal granulations aid in the further erosion
of the bone, whilst the visceral may, according to Macewen,[54] even
indent the brain. By means of thrombosed veins, perivascular lymphatics,
and minute arterioles, a channel of infection is now opened up between
the site of osseous erosion and the temporo-sphenoidal and cerebellar
lobes.

[Illustration: FIG. 74A. DIAGRAM TO SHOW EXTENSION OF DISEASE FROM
TYMPANIC CAVITY, IN MIDDLE EAR SUPPURATION. 1, Perforation through
tympanic membrane; 3, Perforation through Shrapnell’s membrane; 4,
Fistula through outer wall of attic (roof of external meatus); 5_a_,
Extradural abscess; 5_b_, Meningitis; 5_c_, Temporo-sphenoidal abscess;
6, Bulb of jugular (thrombosis); 11, Internal ear; 12, 12_a_, 13, Route
of infection through internal ear giving rise to extradural abscess,
meningitis, and cerebellar abscess. (After Hunter Tod.)]

[Illustration: FIG. 74B. DIAGRAM TO SHOW SURGICAL ANATOMY FOR OPERATIONS
FOR OTITIC INTRACRANIAL LESIONS. 1, Attic; 2, Antrum; 3, Point for
opening temporo-sphenoidal abscess (just above and along the tegmen
tympani); 4, External semicircular canal; 5, Lateral sinus; also shows
area of bone removed in mastoid operation; 6, Bulb of jugular vein; 7,
Facial nerve; 8, Point for opening cerebellum behind lateral sinus; 9,
Point for opening cerebellum in front of lateral sinus (between sinus
behind and external semicircular canal in front). (After Hunter Tod.)]

In any case the abscess usually develops in the white substance of the
brain, just beneath the grey matter, and in close relation to the
primary source of infection.


_The wall of the abscess._ In an abscess of rapid development the walls
are ragged and but ill-defined from the surrounding brain substance. In
the more chronic cases the cavity is shut off from the brain by a
capsule of varying density--usually not more than one-sixteenth of an
inch in thickness, but occasionally of much greater development (see
Fig. 86A). Sometimes--more especially in cerebellar cases--two cavities
may be superimposed, the two abscesses communicating with one another by
means of a narrow, and often tortuous, channel. Successful drainage of
the one cavity may be inadequate to drain its companion. This two-saced
abscess will be again alluded to at a later period.


_Contents of the abscess._ The pus is usually of a greenish hue,
odourless, and acid in reaction. Though often sterile the following
bacteria may be cultivated--_staphylococcus pyogenes aureus_ and
_albus_, _pneumococcus_, _bacillus pyocyaneus_, and the _streptococcus
pyogenes_. The pus is usually of such viscidity that it cannot be
evacuated through the lumen of an ordinary aspirating needle.


_The size of the abscess._ In size the abscess varies greatly, seldom,
however, containing more than 5 or 6 drachms of pus.


_The neck of the abscess._ It was first pointed out by Ballance[55] that
most brain abscesses secondary to disease of the bones of the skull are
‘mushroom-shaped’, the narrow portion or stem being attached to the dura
mater at the original site of infection. The stalked form of abscess is
‘quite comparable, as to its mode of formation, to the superficial
cervical abscess connected by a narrow track to a focus of disease
beneath the deep fascia’.


_Course pursued by an untreated brain abscess._ The abscess enlarges at
the expense of the surrounding tissues, either bursting into the
ventricles of the brain or coming to the surface, there rupturing and
leading to a diffuse meningeal infection. Some few cases have been
reported in which the abscess has established a more or less efficient
natural means of drainage, either along the ‘stalk’ of the abscess or by
means of a new channel to the exterior. In one or two cases,
spontaneous recovery has apparently taken place.


_Mode of healing after successful operation._ Previous to successful
evacuation, the brain immediately surrounding the abscess cavity is
compressed and anæmic. As soon as drainage is supplied, it swells out
like a sponge, more or less obliterating the cavity. The closure of a
cavity by means of the formation of granulation tissue probably never
occurs, and, if the falling together of the surrounding brain is
insufficient to obliterate the cavity, final closure is completed by the
in-dragging of the overlying tissues--scalp, membranes, and brain
becoming intimately fused together.


=Symptomatology.= The symptoms must be considered under the following
headings:--

  The symptoms peculiar to the INITIAL  stage of the abscess
    „    „        „       „    LATENT     „     „       „
    „    „        „       „    MANIFEST   „     „       „
    „    „        „       „    TERMINAL   „     „       „


=The INITIAL stage.= If a patient suffering from brain abscess is
capable of answering questions, it will usually be found that he dates
his illness from some particular day when he was sick, experienced a
shivering attack, or suffered from a severe attack of headache. Further
inquiry, however, will almost always elucidate the fact that, for some
days or weeks previously, he was not feeling well, suffering from
insomnia and loss of appetite, and experiencing occasional attacks of
headache. Friends and relatives may volunteer information as to general
irritability, alteration of manner, incapability of mental
concentration, and worry over family and financial matters.

At this stage the headache is commonly referred to the frontal region,
less frequently localized to the region of the brain involved. The
patient sleeps badly, and there is often a slight rise of temperature
towards the evening. Occasionally he may vomit, independently of the
ingestion of food.


=The LATENT stage.= Mental depression becomes more marked, headache is
more persistent and now shows a definite tendency to localization, food
is distasteful, and bodily wasting becomes evident. The evening rise of
temperature becomes more constant, sickness more frequent, and vertigo
and giddiness may be noticeable features.


=The MANIFEST stage.= The symptoms arising during the manifest stage
must be considered as follows:--

(_a_) Symptoms dependent on the general increase in the intracranial
pressure.

(_b_) Symptoms dependent on the localization of the abscess.

_Symptoms pointing to a general increase of intracranial pressure_

=General mental condition.= In the latent and early manifest stages the
patient will answer questions more or less correctly, but with
hesitation--as if from delayed comprehension and from prolongation of
the latent period. Answers are often inappropriate to the question, and
given with some confusion of mind and thought--the state of
‘slow-cerebration’.

The patient either lies listless and apathetic--mentally dulled--or
exhibits general irritability, lying curled up in bed, intolerant of all
interrogation and examination. More rarely, cerebral irritation
progresses to actual mania, the patient tossing about in bed, muttering
and delirious. Forcible restraint is often required. In the later
manifest stages the patient lies comatose.

=Headache.= Headache is an almost constant feature, varying greatly in
intensity, but often so severe that the patient is incapacitated from
all attempts at conversation and movement. Exacerbations are frequent,
the sufferer crying out in his agony. The pain may be localized or
diffuse. Localization of the pain to some special region is of
considerable aid to the regional diagnosis of the abscess--more
especially so when it is accentuated by palpation and percussion over
the suspected region.

=Vomiting.= Vomiting is another frequent symptom, probably dependent on
stimulation of the medullary vomiting centre. It is of the so-called
‘cerebral’ type, bearing no relation to the ingestion of food and
unaccompanied by previous nausea and retching. The vomited material is
propelled outwards with considerable force. There appears to be some
relation between the exacerbations of headache and the time at which
vomiting occurs. Vomiting is most constantly observed when the abscess
is subtentorial in position.

=Optic neuritis.= It is exceedingly difficult to determine the frequency
with which optic neuritis develops in cases of brain abscess. Much
depends on the site of the abscess and the duration of its existence.
Optic neuritis is seldom absent in the more chronic cases and is most
constant when the purulent collection is subtentorial in position. The
non-appearance of optic neuritis--even in chronic cases--does not
confute a diagnosis of abscess formation.

When once present, the swelling of the disk may increase rapidly. In a
case of cerebellar abscess recently under my care the swelling reached
6D. in three days. Whatever the localizing value of unilateral neuritis
in tumour formation (see p. 216), I am strongly of opinion that in the
cases under discussion, optic neuritis, when confined to or more marked
on the one side, implies that the abscess is situated on that side.

=The pulse and temperature.= It is commonly stated that, in typical
cases of brain abscess, the pulse-rate is slowed--40 to 60 per
minute--and that the temperature is subnormal. Slowing of the pulse
results from stimulation of the medullary centre, the lowering of
temperature to less determinate causes. In the consideration of pulse
and temperature--and the two must invariably be considered together--it
will, however, frequently be found that the temperature is raised and
the pulse-rate but little altered. Thus, in one case the pulse was 88
and the temperature 103·4 degrees, in another the pulse was 74 and the
temperature 102, in a third case the pulse was 89 and the temperature
102·8 degrees. These cases are very significant, and show that the
greatest attention should be paid to a comparison between pulse-rate and
temperature, a _relative_ slowing of the pulse being more constant than
an actual retardation.

The elevation of temperature results from the fact that the great
majority of cases of brain abscess are secondary to some highly
infective purulent collection, as, for instance, a mastoid empyema. In
such a case, if the mastoid region be cleared out, the temperature will
fall and the typical clinical picture of subnormal temperature and
slowed pulse-rate will be depicted.

=The respiration.= The increase of intracranial pressure may lead to
some slowing and deepening of respiration. Irregularity is, however, the
more common condition, deepening, in the later stages, to definite
Cheyne-Stokes respiration. Under anæsthesia--more especially in
cerebellar cases--there is considerable risk of respiratory failure (see
foot-note, p. 238).

=Vaso-motor changes.= Vaso-motor changes are fairly constant, evidenced
by sweats and flushings, _tache cérébrale_, &c.

=Reflexes.= In the earlier stages of the trouble the reflexes may be
increased and Babinski’s sign present. In the later stages, all reflexes
are abolished.

[Illustration: FIG. 75. A LARGE RIGHT-SIDED TEMPORO-SPHENOIDAL ABSCESS.]

=Other more general symptoms.= Obstinate constipation, foul tongue and
breath, anorexia, deficient urine, loss of bladder and rectal control,
are all noticeable features. A well-marked leucocytosis is generally to
be observed.

_Symptoms dependent on the localization of the abscess_

(_a_) =Temporo-sphenoidal abscess.= The abscess occupies one of the
so-called ‘silent’ areas of the brain, an area merely exercising a
word-hearing faculty (see p. 163). Insomuch, however, as auditory power
is already impaired or lost from the disease existent in the middle ear,
it follows that a temporo-sphenoidal abscess may not give rise to any
localizing symptoms whatever. Definite motor symptoms will only be
observed when an abscess of considerable size exercises an upward
pressure on the lower motor areas, or an inward pressure on the internal
capsule. Thus, (1) when the pressure effects are exercised in the
_upward_ direction the lower motor areas will suffer with resultant
paresis or paralysis of the muscles of the contra-lateral face and upper
extremity, and, if the abscess be situated on the left side, aphasia may
also be present. And (2) when the pressure is exerted mainly in the
_inward_ direction so as to interfere with the internal capsule the
motor areas are affected in the reverse order, lower extremity first and
face last.

[Illustration: FIG. 76. TO ILLUSTRATE THE PRESSURE EFFECTS OF A
TEMPORO-SPHENOIDAL ABSCESS:--(1) _upward_ pressure on the lower cortical
motor area, and (2) _inward_ pressure on the internal capsule. T.S.,
Temporo-sphenoidal abscess; _a._, Cortical area for lower extremity;
_b._, Cortical area for upper extremity; _c._, Cortical area for face;
C.N., Caudate nucleus; L.N., Lenticular nucleus; I.C., Internal capsule;
O.T., Optic thalamus.]

_Aphasia_ will partake of the motor or sensory type according to the
situation of the abscess. Thus, motor aphasia indicates pressure on
Broca’s area, sensory points to the involvement of the region of the
angular gyrus (see p. 163). According to Schmiegelow, some type of
aphasia was present in 23 out of 54 cases of otitic temporo-sphenoidal
abscess.

_Facial paralysis_, whether due to inward or upward pressure, is of the
incomplete or cortical type, the upper face-muscles escaping or being
but slightly affected. No difficulty need be experienced in
differentiating between the ipso-lateral paralysis which results from
destruction of the facial nerve in the aqueductus Fallopii and the
contra-lateral palsy dependent on the cortical lesion.

Pressure may also be exercised on the post-Rolandic sensory areas and on
the tracts that evolve therefrom, but the general condition of the
patient seldom allows of any accurate diagnosis with respect to sensory
involvement in general.

When the abscess is of considerable size, both _third_ and _sixth_
nerves may be involved. For instance, the third nerve, emerging from the
brain at the anterior border of the pons, and passing along the inner
border of the temporo-sphenoidal lobe, is liable to irritation or
pressure paralysis. In the former case, the pupil on the affected side
will be contracted, in the latter instance dilated. When _ipso-lateral_
third nerve paralysis coexists with paralysis of the opposite face and
upper extremity, a condition of crossed paralysis results.

When the sixth nerve is involved the external rectus on the side of the
lesion is paralyzed with resultant internal squint. Conjugate deviation
of the eyes towards the side opposite to the lesion and secondary
lateral nystagmus have both been observed.

Further assistance in the localization may be obtained by careful
observation as to the position of the headache, by palpation and
percussion of the skull, and by a comparison of the intensity of optic
neuritis in the two disks.

(_b_) =Cerebellar abscess.= Many of the symptoms previously described
when dealing with brain abscess in general are intensified when the
focus of suppuration is situated in the confined space beneath the
tentorium cerebelli. Thus, headache is exceptionally severe and more or
less localized to the occipital and cerebellar regions. Again, optic
neuritis may develop rapidly and reach a high grade of intensity,
vomiting is early in onset and of frequent occurrence, whilst certain
other symptoms dependent on the increased intracranial pressure--slowing
of the pulse, alterations in respiratory rhythm--are correspondingly
accentuated.

The more typical _localizing_ symptoms are as follows:--

_Vertigo_ is a prominent symptom, most evident on sudden alteration of
position on the part of the patient. He complains, for instance, of
great giddiness on sitting up in bed. The sensation of movement may be
of self or of objects.

[Illustration: FIG. 77. A CEREBELLAR ABSCESS.]

When standing, he tends, when unsupported, to fall or lurch in some
particular direction, more commonly, in my experience, towards that side
on which the abscess is situated. On this point, however, there is some
difference of opinion and, by itself, it cannot be accepted as having
any great localizing value.

In some rare cases Dana’s symptom may be noticed--a sudden unexpected
attack of vertigo, roaring in the head, relaxation of limbs, and falling
to the ground in an unconscious state. This symptom is said to be almost
pathognomonic of an abscess (or tumour) situated in the region of the
cerebello-pontine angle.

The _cerebellar gait_ can of course only be demonstrated when the
patient is in a fit condition to walk. He shows, by the position of the
feet, a desire to obtain a wide base of support and staggers on, in his
desire to carry out his instructions, usually inclining towards the side
on which the lesion is situated. This inclination is probably dependent
on the weakness of the muscles of the ipso-lateral side (see below).
Another important feature may be observed in the tendency on the part of
the patient to turn the head in such a way that he faces somewhat in the
opposite direction, the chin being directed towards the opposite
shoulder.

_Disturbances of co-ordination_ may be demonstrated by telling the
patient to touch the tip of his nose with his finger, or to strike at an
object held a foot or two in front of him. Such attempts are
characterized by uncertainty and irregularity of movement, accompanied
by considerable tremor.

_Paresis or paralysis of the limbs on the ipso-lateral side._ The
abscess usually occupies the antero-external aspect of the lateral lobe
of the cerebellum, and is so situated that no direct pressure is
exercised on the pyramidal fibres. Some weakness--perhaps paralysis--of
the muscles of the extremities on the same side as the lesion can,
however, usually be demonstrated. According to Luciani, this is
explained in the following manner:--between the cortex of the one side
and the cerebellum of the other there are certain ‘associated’ fibres,
the strength of the impulses sent out from the cortex depending in part
on the integrity of these reinforcing cerebellar fibres. In cases of
cerebellar abscess these reinforcements are cut off with consequent
paresis, or even paralysis, of the muscles of the face, arm, and leg on
the same side as the lesion. Associated with this muscular weakness
there is usually some increase in the deep reflexes. Some of the
pyramidal fibres do not decussate, and, consequently, an ipso-lateral
paralysis may be associated with a contra-lateral paresis.

The same lessening of cortical impulses accounts for a weakening in the
external rectus of the same side, which muscle, acting with the internal
rectus of the sound side, allows of a conjugate deviation of the eyes
towards the opposite side, with well-marked _nystagmus_--of a coarse
type--on attempting to correct this deviation.

[Illustration: FIG. 78. A DIAGRAMMATIC ILLUSTRATION (AFTER LUCIANI) TO
EXPLAIN THE SYMPTOMS OBSERVED IN CEREBELLAR ABSCESS FORMATION. P.,
Pyramidal fibres; C.A., Right cerebellar abscess; R., Reinforcing fibres
from right cerebellum to left cortex; B.g., Basal ganglia; E.R.,
External rectus; N., Nucleus for sixth nerve; D.P.T., Direct pyramidal
tract; C.P.T., Crossed pyramidal tract.]

_Retraction of the head and neck._ Retraction of the head and neck,
stiffness of the nuchal muscles, and even opisthotonos, may be
observed. The existence of these symptoms is always suggestive of
meningeal infection, but an abscess of considerable size, even when
situated in the anterior part of the lateral lobe of the cerebellum, may
so exercise pressure in the downward direction as to cork up that part
of the cerebellum which normally extends into the mouth of the foramen
magnum. The neighbouring upper cervical nerves may then be irritated or
compressed.

_Yawning._ Frequent purposeless yawning is said to be pathognomonic of
cerebellar disease (see p. 165).

_Attitude in bed._ More commonly the patient lies curled up in bed in
the position of cerebral irritation, perhaps more frequently with the
sound side upwards.

(_c_) =Frontal abscess.= The abscess is usually dependent on
long-continued suppuration in the frontal sinus, with deficient drainage
and spread of disease to the surrounding bone. The abscess may be
situated in close relation to the focus of the disease, but, more
commonly, it occupies a more posterior position, so much so that direct
pressure is exercised on the corona radiata proceeding from the
pre-Rolandic or motor area. It would appear also that definite
localizing symptoms do not arise until the abscess has attained
considerable size. The _general symptoms_ peculiar to all cases of brain
abscess are perhaps less definite when the abscess is frontal in
position. Thus, although headache may be localized to the frontal
region, and although optic neuritis may be present, yet vomiting,
alterations in pulse-rate and in respiratory rhythm are less marked than
usual.

The _localizing symptoms_ are often reasonably definite, so much so that
but little difficulty may be experienced in arriving at a diagnosis.

In the earlier stages of the abscess formation motor irritation may
predominate, with the development of _fits of the Jacksonian type_, the
lower and more anterior motor areas being first and mainly affected.
More commonly, however, attention will be directed towards the nature of
the trouble by _paresis or paralysis of the opposite side of the body_.
In this case also the lower motor areas--those responsible for the
opposite side of the face and upper extremity (also the motor
speech-area on the left side of the brain)--are first and chiefly
involved. In some cases--more especially when the abscess is of
considerable size--definite hemiplegia may result.

In cases of frontal abscess, the _mental condition_ of the patient
demands special consideration. Some definite degree of moral perversion
will usually be noticed, the patient--presuming that he is in a
conscious condition--making himself as objectionable as possible. He
will upset his food, disarrange his bedclothes, disobey orders, and even
pass his urine and fæces in his bed though well aware of his
wrong-doing. When questioned he answers with suspicion, when examined he
demands to know the why and the wherefore of the various details of the
investigation. An ophthalmoscopic examination is especially difficult to
carry out in a satisfactory manner. In a case recently under my
care--one in which a frontal abscess was drained three times before a
cure was obtained--these curious mental perversions were observed each
time, and the patient subsequently acknowledged that he had performed
the various acts wittingly, but was unable to deny himself the
opportunity of irritating those around him.

It has been stated that these mental changes are only to be observed
when the abscess involves the _left_ frontal lobe. In my own experience
no such lateral differentiation has been noticed.

_Anosmia_ may be present if the patient is in a condition to respond to
the tests requisite to prove the defect. In most cases, however,
considerable difficulty will be experienced in applying the tests, and
the results obtained are too variable. Anosmia will be associated with
impaired power of taste.

_Pupillary changes._ ‘If the abscess is of large size, the pupil on the
same side is in a state of stabile mydriasis; if small, it may be
sluggish and contracted.’[56]


=The TERMINAL stage.= In _fatal_ cases death results from the pressure
exercised by the expanding abscess on the bulbar centres, or from the
bursting of the abscess into the ventricular or meningeal spaces. During
this terminal stage the pulse becomes very rapid, the respiration
irregular and Cheyne-Stokes in character, whilst the temperature rises
rapidly, reaching 105-110 degrees F. Invasion of the lateral ventricle
is evidenced by violent convulsions, rigidity of the extremities,
opisthotonos, retraction of the head, trepidation, and prostration. The
pupils become widely dilated, and remain in that condition till death
ensues.


=Treatment.= In the operative treatment of _otitic temporo-sphenoidal
and cerebellar abscess_ two courses are available:--(1) to trephine
directly over the abscess through the squamous or cerebellar regions,
postponing mastoid exploration till a later date (the two-stage
operation); and (2) to carry out the complete mastoid operation,
searching for the ‘stalk’ of the abscess, and draining the abscess into
the now-united middle ear and antrum (the one-stage operation).

The former course is advocated by many general surgeons, the latter is
the one usually pursued by the aural surgeon. The advantages claimed for
the former method--the direct trephining method--are as follows:--

(1) The general condition of the patient is often of so serious a nature
as to prohibit the more prolonged procedures essential to the mastoid
exploration.

(2) When the exploration is conducted from the infected middle ear, an
unsuccessful attempt to find the abscess carries with it an appreciable
risk of meningeal and brain infection. Unsuccessful exploration through
the ‘clean’ squamous and cerebellar regions presents no such
disadvantages.

(3) The drainage as supplied through the trephine hole is often superior
to that provided by dilating up the ‘stalk’ of the abscess into the
middle ear.

(4) Many general surgeons do not possess that intimate acquaintance with
the anatomy of the ear which is necessary to carry out a complicated
aural operation.

Each case must be considered on its own merits, but I am inclined to
advocate the two-stage method when the diagnosis is reasonably clear
that the patient is suffering from temporo-sphenoidal or cerebellar
abscess, mastoid exploration being carried out as soon as the patient
has recovered from the first operation. When, however, considerable
doubt exists as to the position of the abscess--or the nature of the
complication in general--it is then advisable to start by exploration of
the mastoid and aural regions, further measures being adopted according
to the conditions found at the time of operation.


1. The two-stage operation.

_Trephining for temporo-sphenoidal abscess._ A point is chosen on the
scalp which lies between 1¹⁄₂ and 2 inches above the centre of the
external auditory meatus, and a bradawl is there introduced so as to
indent the external table of the skull. A small scalp-flap is framed,
one presenting an upward convexity, and all bleeding controlled. The pin
of the trephine is applied to the spot previously indicated on the bone
and the disk removed. On account of the absence of diploic tissue and
consequent approximation of the two tables of the skull, care must be
taken to avoid injury to the posterior branch of the middle meningeal
artery and to the bulging dura mater.

[Illustration: FIG. 79. THE EXPOSURE OF A TEMPORO-SPHENOIDAL ABSCESS.]

The dura is then inspected and palpated; absence of pulsation, loss of
lustre and tenseness, indicate the probable adjacency of the abscess
cavity. The membrane should be crucially incised, all meningeal vessels
that cross the line proposed for section being first under-run on either
side of that line. The scalpel is lightly applied to the membrane and,
as soon as the pia-arachnoid is exposed, the section completed with the
blunt-pointed scissors.

The four dural flaps are turned aside and the cortex exposed. At the
very apex of the bulging brain, and avoiding all visible vessels, a
large blunt-pointed trocar and cannula or, preferably, Horsley’s
pus-evacuator is introduced and passed, for not more than 1¹⁄₂ inches,
in a direction inwards and slightly forwards, parallel to the roof of
the middle ear. The blades of the evacuator must be opened ‘once for
each quarter of an inch of brain substance penetrated’ (Macewen). If the
trocar and cannula be utilized, similar precautions must be adopted.

In the event of failure to find pus at the first attempt, the evacuator
is withdrawn, introduced at the same site, but now passed in other
directions--directly inwards, slightly upwards, and finally, slightly
backwards, in each case for not more than 1¹⁄₂ inches.

By wide separation of the blades of the evacuator the pus is allowed to
escape, to be immediately wiped away by the assistant. Irrigation of the
cavity should never be attempted, not so much because of the
difficulties attendant on that process, but because of the danger of
infecting the neighbouring meningeal regions.

Previous to withdrawal of the evacuator, a small rubber or cigarette
drainage-tube is introduced, projecting into the abscess cavity at the
one end, and brought out through the scalp-flap at the other. It is
advisable to stitch the tube in position.

The dural flaps are replaced in their proper position, but no attempt is
made at sewing them together. The scalp-flap is sutured with the aid of
a few salmon-gut stitches and the dressings applied. The tube may be
shortened daily, and dispensed with after seven to ten days, according
to the progress of the case.

_Trephining for cerebellar abscess._ The abscess usually occupies the
antero-external aspect of the lateral lobe of the cerebellum. It can be
drained with advantage below the level of the lateral sinus and behind
the posterior border of the mastoid process.

The patient should be in the semi-prone position, the head as forwardly
flexed as the administration of the anæsthetic allows.

The incision starts below the external occipital protuberance, and,
following the line of the occipital crest, curves downwards along the
posterior border of the mastoid process, terminating at the apex of that
prominence. The cutaneo-muscular flap is turned down, every precaution
being taken to diminish hæmorrhage, insomuch as severe bleeding may take
place from occipital vessels, and from the mastoid and other emissary
veins. Hæmorrhage from the former source is controlled with forceps,
that from the emissary veins by the introduction of the end of a blunt
probe into the orifice of the foramen. More permanent occlusion can be
obtained by plugging the foramen with catgut, with a sterilized wooden
match, or by means of special ivory, bone, and wooden pegs.

The trephine is applied in such a manner that its circle falls well
below the lower level of the lateral sinus and behind the mastoid
process. After removal of the disk, the dura mater is cautiously opened
by crucial incision and the evacuating instrument introduced, the
cerebellum being explored in the forward and slightly inward
direction--towards the posterior aspect of the petrous bone. The abscess
should be reached within 1¹⁄₂ inches from the opening in the bone. A
drainage tube is introduced, stitched in position, in the manner
described when dealing with temporo-sphenoidal abscess. This tube should
be shortened daily and dispensed with after seven to ten days.

_Trephining for frontal abscess._ An abscess of the frontal lobe is
generally situated so far back, and connected with the source of the
trouble (the frontal sinus) by so long a ‘stalk’ of infection, that
considerable difficulty may be experienced in attempting drainage from
the frontal or nasal regions. Moreover, operations conducted through the
frontal region are apt to result in considerable deformity. The
operation may therefore be conducted with advantage from the
temporo-frontal region. In this situation, the bone is thin, the
operation can be conducted between the split fibres of the temporal
muscle, excellent drainage is supplied, and the scar is inconspicuous.

For a general description of the intermusculo-temporal operation, the
reader is referred to p. 121. In this instance, the field of operation
is shifted further forwards, otherwise the details are very similar. The
skin incision commences above and in front of the external angular
frontal process, curves along the temporal crest, and terminates well in
front of the ear. The temporal fascia is turned down and the muscle
split in the general direction of its fibres, and well retracted on
either side. The trephine is applied, the dura mater incised, and the
abscess evacuated and drained in the manner previously described. The
tube may be removed after seven to ten days.

_The treatment of a chronic encapsuled abscess, wherever situated._ In
attempting to evacuate a chronic encapsuled abscess, both the trocar and
cannula and the evacuator merely impinge against, and tend to push
aside, the dense enclosing wall of the abscess cavity. When such
obstruction is suspected, a director should be introduced in the
direction of the abscess, and the brain explored till the resistance of
the abscess-wall is encountered. With the aid of two narrow spatulæ, or
other suitable instrument, the passage through the brain is gently
enlarged till the wall of the abscess becomes visible. The margins of
the passage through the brain are gently retracted and the abscess-wall
freely incised with the knife. After the evacuation of the pus, a
drainage tube can be introduced, but, as such a method seldom permits of
a permanent cure--the abscess filling up again as soon as the tube is
withdrawn--it is generally advisable to attempt the entire removal of
the abscess-wall. The cut edges of the capsular incision are seized with
narrow-bladed forceps, gentle traction applied, and the surrounding
brain substance carefully peeled away. As a rule, there is no great
difficulty attendant on this process and the hæmorrhage is seldom
severe. The cavity that remains in the brain substance is _lightly_
packed with gauze, this packing being allowed to remain for twenty-four
to thirty-six hours, after which it is withdrawn and a little fresh
gauze introduced, if necessary. The cavity fills up with extraordinary
rapidity, mainly as a result of the expansion and falling together of
the surrounding brain (see Figs. 86 and 86a).


2. The one-stage operation.

_Preliminary exploration of the mastoid operation, followed by an
investigation of the middle and posterior fossæ of the skull._ To expose
the mastoid antrum, the incision commences immediately above and behind
the ear, and, carried down to the bone throughout, terminates near the
tip of the mastoid process. The soft tissues are peeled away in the
forward direction and the cartilaginous ear detached from the posterior
and upper boundaries of the bony auditory meatus.

Macewen’s suprameatal triangle and the supramastoid crest are
identified, the former landmark being taken as a guide to the
communication between the mastoid antrum and the middle ear, the latter
representing the uppermost limit of the field of operation.

[Illustration: FIG. 80. THE ‘RADICAL’ MASTOID OPERATION. To show removal
of the ‘bridge’ from above. The seeker, inserted into the aditus, acts
as a protector to the underlying external semicircular canal and facial
nerve. (After Hunter Tod.)]

With the aid of the hammer and chisel the bone is chipped away till the
antrum is exposed--on an average this will be situated about
three-fifths of an inch deep from the surface. The opening necessarily
becomes funnel-shaped, but it should be made as complete as
circumstances permit.

As soon as the antrum is exposed, the seeker or nerve-protector should
be introduced into the aditus, acting as a protector to the underlying
external semicircular canal and facial nerve, and the ‘bridge’ of bone,
which now intervenes between the antrum and the middle ear, chiselled
away, in the manner indicated in Fig. 80.

The field of operation is now carefully cleansed, cholesteatomata,
bone-debris, and ossicles being gently removed, and--with the aid of a
head-lamp--a careful search instituted for fistulous tracts, carious
bone, &c. This search must be carried out with the greatest gentleness
for fear of inducing further complications.

Subsequent procedures vary according to the nature of the conditions
found. Thus:--

1. When the diagnosis is uncertain and when the boundaries of the cavity
appear fairly healthy, the operation may terminate at this point, a
post-meatal flap being formed and the cavity lightly plugged with gauze.
The proximal end of the gauze plug is brought out through the enlarged
auditory meatus and the ear-flap sewn back with a few salmon-gut
sutures.

[Illustration: FIG. 81. EXPLORATION FOR A TEMPORO-SPHENOIDAL ABSCESS. A,
Above the tegmen tympani; B, Through the tegmen tympani. Occasionally
these methods are combined; the bone between the openings being also
removed. (After Hunter Tod.)]

2. When the evidence points to implication of the _middle_ fossa, the
scalp incision is prolonged upwards for about 1 inch and the soft parts
retracted. The supra-tegmental extra-dural space can be exposed either
by chiselling away the osseous roof of antrum and middle ear, or by
means of a separate opening above the level of the supramastoid crest.
In the event of the discovery of an _extra-dural_ collection of pus, the
purulent material is gently wiped away, free drainage supplied, and the
wound closed.

In both this and the preceding case, the progress of the case during the
ensuing twenty-four to forty-eight hours will prove whether adequate
measures have been adopted.

When the symptoms are suggestive of _brain abscess_, when no extra-dural
collection is discovered, and when the dura mater is tense and
discoloured, then it becomes necessary to explore the brain. This can be
carried out through an opening made in the tegmen or above the level of
the supramastoid crest. Which route should be utilized depends on the
local conditions. As a general rule, it is advisable to explore through
the tegmen when a sinus exists in that situation, and above the
supramastoid crest under all other circumstances.

[Illustration: FIG. 82. EXPLORATION FOR A CEREBELLAR ABSCESS. A behind,
and C in front of the lateral sinus; B, Lateral sinus. (After Hunter
Tod.)]

In the latter case, the dura mater is incised crucially and the bulging
brain explored in the manner indicated on p. 266. The mastoid region
should first be cleansed and packed with gauze, but, even with such
precautions, it is obvious that there is some risk of contaminating
membranes and brain in the event of failure to discover the abscess
cavity--an argument in favour of exploring through the ‘clean’ squamous
region (see p. 264).

3. When the evidence points to implication of the _posterior_ fossa, an
incision is carried backwards, from the mid-point of the post-aural
incision, for about 2 inches, and the soft parts retracted upwards and
downwards. With the chisel (or gouge) and hammer, the bone is freely cut
away so as to expose (1) the lateral sinus, and (2) the dura mater below
and behind the curve of the sinus. As soon as the sinus is exposed, the
dura mater may be separated from the bone and the subsinus region
exposed with the aid of craniectomy forceps.

The extra-dural space between the posterior aspect of the petrous bone
and the lateral sinus region is first inspected, and, in the event of
the discovery of a collection of pus, this is gently wiped away and
further exploration postponed till the occasion should prove the
necessity.

When the indications are of such a nature as to demand _exploration of
the cerebellum_, the mastoid region is first cleansed and packed with
gauze, after which the dura mater is incised either in front or behind
the sinus according to the probable situation of the abscess cavity.
After the evacuation of the abscess a drainage tube is stitched in
position in the manner previously indicated.


Difficulties and dangers attendant on the process of trephining for
brain abscess.

  _Failure to find the abscess_ is usually dependent on one of the
  following causes:--

  (_a_) The abscess may be missed if the localizing features are
  misleading, if the abscess be small, and if the exploring instrument
  be passed in a faulty direction or to an insufficient depth.

  (_b_) The abscess may be traversed but not tapped if unsuitable
  exploring instruments be used--an aspirating syringe, for instance,
  through which the thick pus will not pass. Even when suitable
  instruments are used, the attempt to evacuate the abscess may fail if
  the operator does not carry out what may be called a system of
  progressive exploration, that is to say, if he does not periodically
  open the blades of the evacuator (see p. 266).

  (_c_) The abscess may be encountered but not penetrated if the surgeon
  has to deal with a chronic abscess, the wall of which is merely
  pushed aside by the advancing instrument (see chronic abscess of the
  brain, p. 268).

  _Complications_ arising during and after the evacuation of the abscess
  are as follows:--

  1. Leaking into the pia-arachnoid and the development of general
  meningeal infection.

  2. Perforation of the ventricular spaces.

  3. Hæmorrhage.

  4. Respiratory failure.

  5. Osteomyelitis of the neighbouring diploic tissue.

  _General meningeal infection_ will bring about a fatal result.
  Fortunately, the general rise of intracranial pressure and the
  formation of adhesions between the brain and the overlying membranes
  tend to prevent its development.

  _Perforation of the ventricular spaces_ may occur under two
  conditions: (1) when the abscess is associated with internal
  hydrocephalus, and (2) when the exploring instrument is passed too
  far.

  _Hæmorrhage_ is seldom serious when the operation is carried out with
  a light hand, all visible vessels being carefully avoided. In the
  event of its occurrence, it may be controlled by lightly packing the
  cavity with gauze.

  _Respiratory failure_ is most liable to occur when the surgeon is
  operating for cerebellar abscess. In the event of its occurrence the
  surgeon should complete his trephining with the utmost expedition,
  thus relieving the intracranial pressure. Under favourable
  circumstances, the respiratory rhythm is soon restored. In the more
  serious cases, artificial respiration should be attempted whilst the
  surgeon carries on his manipulations, opening the skull as rapidly as
  possible.


MENINGITIS

Previous to entering into the question of general meningeal infection,
some allusion must be made to the rarer forms of meningitis.


=Serous meningitis.= Quincke demonstrated in 1895 the existence of a
serous form of meningitis, one characterized by a sero-fibrinous
exudate. He showed that, just as we have to deal with a serous or
purulent pleurisy, so we have to consider the possibility of a serous or
purulent form of meningitis.

The exudate appears at first sight to differ but slightly from normal
cerebro-spinal fluid, being clear, yielding the normal chemical
reactions of that fluid, and occupying the subarachnoid region. Later on
it becomes slightly turbid, contains a fair quantity of albumen, and is
proportionately rich in cellular elements--lymphocytes and
polymorphonuclear leucocytes. The membranes are swollen, the vessels
dilated, whilst occasionally many minute hæmorrhages may so allow of the
escape of red blood-corpuscles as to impart to the exudate a
yellowish-red coloration. At a still later stage the exudate becomes
flocculent as a result of the deposition of a fibrinous coagulation, a
gum-like material forming over the surface of the brain.


=Pachymeningitis externa.= Pachymeningitis externa is almost necessarily
dependent on disease of the middle ear, on suppuration in the accessory
sinuses of the nose, and on infected fractures of the vault and base.
The inflammatory changes primarily involve the external aspect of the
dura mater, the external surface of which is injected, roughened with
fibrinous exudate, and, in the more chronic cases, covered with
granulations. In itself the process seldom gives rise to symptoms, but
so soon as the inner surface of the dura shares in the affection
(meningitis), or the infection spreads to the venous sinuses (sinus
thrombosis), or to the brain (brain abscess), definite symptoms arise
pointing to the nature and character of the change.


=Pachymeningitis interna and pachymeningitis interna hæmorrhagica.= As
the direct result of alcoholic excess, of syphilitic infection, and of
trauma, the inner surface of the dura mater loses its shiny appearance,
becomes opaque and thickened, especially in the region of the falx
cerebri and over the convexity of the brain. The sodden and œdematous
condition of the dura gives rise to a fibrinous and membranous exudate,
terminating in the formation of false membranes--one of the factors in
the formation of so-called ‘arachnoid cysts’ (see p. 203). These
membranes are seen to be attached to the dura mater by means of
newly-formed vessels, some of which may rupture, giving origin to blood
exudate sufficing to impart to the membranes a brownish-red coloration.
In the more marked cases, especially in those of a recurrent nature, the
membranes partake of a lamellated type. Occasionally, the hæmorrhages
are more excessive, giving rise to the formation of subdural hæmatomata
from the partial absorption of which the various types of
pachymeningitis hæmorrhagica arise.

These rarer forms of meningitis seldom give rise to such definite
symptoms as to allow the surgeon to carry out surgical procedures in
their earlier stages. Later on, by reason of the development of cystic
accumulations of fluid or other complication, operation may be carried
out with a reasonable degree of success. The operative technique
adapted to the individual case is discussed under appropriate
headings--Jacksonian epilepsy, meningeal cysts, &c.

It is possible that some criticism may be aroused with regard to the
non-inclusion of tuberculous meningitis. Insomuch, however, as I have
operated on a considerable number of cases of tuberculous
meningitis--some intentionally from a decompression point of view,
others by reason of doubtful diagnosis--and have never brought about
more than some temporary alleviation, I have come to regard such cases
as beyond the realms of surgery.

[Illustration: FIG. 83. A FRACTURE OF THE ANTERIOR FOSSA WHICH WAS
FOLLOWED BY THE DEVELOPMENT OF MENINGITIS.]


=Acute lepto-meningitis.= This condition will be considered under the
more familiar, though less correct, designation--_meningitis_.

Attempts have been made to classify the various forms of meningitis on a
bacterial basis. When, however, it is realized that almost any known
form of organism may be present in the exudate, and that the symptoms
dependent on these various infections closely resemble one another,
merely differing in their acuteness and intensity, it would appear that
some other form of classification is preferable.

The following method of classification will suffice:--


=1.= =Meningitis of traumatic origin.= The organisms either obtain
direct entrance to the meningeal space by means of a compound fracture
of the vault or base of the skull, or reach their destination along the
course of the numerous emissary and diploic veins that bring the extra-
and intra-cranial channels into communication.


=2.= =Meningitis secondary to disease of neighbouring regions.=

(1) The accessory sinuses of the nose and ear.

(2) The bones of the skull.

(3) The soft parts--scalp, orbit, nose, and face.


=3.= =Meningitis secondary to disease of more distant regions.= Through
the medium of the blood-stream bacteria may be carried to the meningeal
region in many acute infections--more especially in diseases of the
lung.


=Some anatomical considerations of meningitis.= The _pia_ is closely
applied to the surface of the brain, dipping down into all the fissures,
both major and minor. The _arachnoid_ is only reflected into the greater
fissures--the mesial longitudinal fissure, the fissure of Sylvius,
Rolando, &c. The pia and arachnoid are therefore separated from one
another by a potential space over the convolutions themselves, and by an
actual space in the region of many of the cortical fissures.

On the under aspect of the brain the two membranes are so disposed and
so separated from one another as to form three great basins or cisternæ,
three great spaces acting as a water-bed for the brain. These are the
_cisterna magna_, the arachnoid bridging over the wide interval between
the back part of the under surface of the cerebellum and the medulla,
the _cisterna pontis_, the angular space between the pons, medulla, and
cerebellum, and the _cisterna basalis_, the arachnoid there covering in
the structure situated in the interpeduncular space, including the
Circle of Willis.

The subarachnoid space, both cortical and basal, is traversed by
numerous trabeculæ which, passing from one membrane to the other, break
up the space into innumerable small compartments, all containing
cerebro-spinal fluid and all intercommunicating. The cerebral vessels
ramify in the space, the tributaries being supported by the framework
and bathed in the fluid.

All cranial nerves carry with them in their emergence from the skull a
process of both pia and arachnoid, variable in extent, but so arranged
that the nerve trunk is surrounded for some distance by a funnel-shaped
process of membrane, the cerebral cerebro-spinal fluid being thus
brought into connexion with the cervical lymphatic spaces.

With respect to the origin of the cerebro-spinal fluid and its wave of
flow, the researches of Leonard Hill tend to prove that it is formed
from the lining ependyma and choroid plexuses of the three main
ventricles of the brain, passing thence into the spinal cerebro-spinal
region and, by means of the foramina of Majendie, Key, and
Retzius--apertures in the roof of the fourth ventricle--on to the
surface of the brain. From this latter region there appears to be a
general tendency for the fluid to pass upwards from the basal aspect of
the brain towards the superior longitudinal sinus where it is again
absorbed, probably through the medium of the Pacchionian bodies and
lacunæ laterales of the venous sinus.

[Illustration: FIG. 84. BASAL MENINGITIS SECONDARY TO TEMPORO-SPHENOIDAL
ABSCESS.]

From these few anatomical facts it is manifest (1) that a subarachnoid
purulent effusion has every opportunity of spreading widely over the
surface of the brain, and (2) that inflammation and its results in the
immediate neighbourhood of the roof of the fourth ventricle will tend
to impede the normal flow of cerebro-spinal fluid through the foramina
in that region, thus inducing a degree of internal hydrocephalus
directly proportionate to the degree of obstruction.

Furthermore, it is obvious that the anatomical arrangements are entirely
opposed to the possibility of providing adequate drainage in cases of
general meningeal infection. It has been suggested that trephine holes
should be made on either side of the skull, and that the intervening
meningeal space should be washed out between the two apertures. It is,
however, impossible to attain such a result, not only because of the
futility of attempting to wash through the subarachnoid meshwork, but
also on account of the outward bulging of the brain substance through
the trephine holes and the corking up of those apertures.

The pus rapidly spreads over the surface of the cerebrum and over the
base of the brain, along the sheaths of the emerging cranial nerves, and
down the spinal canal. Associated with vascular dilatation there is
extensive leucocyte extravasation into the perivascular spaces, the
course of the line of the attack being mapped out by white and yellow
lines and areas of exudation. Insomuch, also, as the meningeal vessels
are in direct continuity with those of the cortex itself, it follows
that a well-developed case of meningitis implies a corresponding degree
of cerebritis, with red or white softening of the brain substance
according to the degree of hæmorrhagic extravasation.


=Symptomatology.= Meningitis is generally sudden in onset and ushered in
by a rigor, frequently of a most intense character. Headache is always a
marked feature, commonly diffuse, but sometimes localized to the region
primarily and mainly affected. The headache is intense and exacerbations
are marked, the patient crying out in his agony. There is great mental
irritability and all attempts at clinical examination are strenuously
resisted.

After the initial rigor the temperature remains high, with occasional
remissions during the early hours of the morning. Vomiting may be
frequent and violent, but, according to my observations, this has not
been a conspicuous feature.

The pulse-rate is increased, whilst, in the early stages, the volume is
full and the tension high. The skin is burning hot and dry, except
during the post-rigor periods when sweating predominates.

The face is flushed, often turgid, and the eyes are bright. General
restlessness is a marked feature.

The more _localizing_ features may be arranged in three groups:
intellectual, motor, and sensory.


=Intellectual symptoms.= The condition of the patient is one of great
restlessness, increasing sometimes to actual violence and mania.
Attendants are usually required to restrain his movements, and, tossing
about in bed, crying out in his pain, muttering and wandering in his
delirium, he offers a typical clinical picture of cerebral irritation.


=Motor symptoms.= The motor symptoms vary according to the region mainly
involved, cortex or base. In the _former_ case, excitation results in
twitchings and convulsions of the regions supplied by the cortical areas
involved. Convulsions may be general or confined to a certain group of
muscles, the former condition usually present in children, the latter
more often observed in adults and occasionally partaking of the
Jacksonian type. Convulsions may be associated with contractures of the
limbs, the flexors mainly affected in such a manner that an attitude of
general flexion may be assumed. The patient appears to suffer pain when
attempts are made to straighten the limbs. In any case, such attempts
are resisted.

Implication of the _base of the brain_. This is evidenced by symptoms
sufficiently definite. Thus, the following symptoms may be observed:--

_Optic neuritis._

_Myosis and squints_, from involvement of the third, fourth, and sixth
nerves.

_Trismus_, from implication of the third division of the fifth nerve.

_Facial paralysis_, from implication of the seventh nerve.

_Deafness_, from involvement of the eighth nerve.

_Dysphagia and dyspnœa_, from involvement of the ninth and tenth nerves.

_Rigidity of the neck and torticollis_, from involvement of the eleventh
nerve.

_Retraction of the head and neck_, from involvement of the posterior
divisions of the upper cervical nerves.

_Opisthotonos_, from the involvement of the posterior divisions of the
upper cervical nerves, sometimes of so excessive a nature that the body
is bent backwards to such a degree that the head and heels are almost
brought into contact. More rarely, pleurosthotonos or lateral flexion is
observed.


=Sensory and other phenomena.= Amongst such symptoms may be mentioned
cutaneous hyperæsthesis, photophobia, and vaso-motor changes--the
last-named evidenced by flushings, sweats, and _tâche cérébrale_.

Rapid emaciation, anorexia, and distaste for all nourishment are the
rule, whilst retention of urine, albuminuria, and glycosuria have been
observed.

The reflexes, both deep and superficial, are often increased. Kernig’s
sign is generally present.


=The period of depression.= The acute stage seldom persists more than
two or three days, the period of excitation giving place to that of
depression. The transition is usually of a rapid nature. The depression
stage is dependent on exhaustion of the cortical and basal centres.

The temperature remains high, rising towards the evening and falling a
degree or more in the early hours of the morn. Death usually takes place
when the temperature is at its highest.

The pulse may become slower as the intracranial pressure increases, but,
more commonly, as the result of toxic poisoning, the rate increases
whilst the rhythm becomes irregular and the tension lowered.

Respiration may partake of the Cheyne-Stokes type, whilst the impaired
æration of the blood and the weak action of the heart are evidenced by
cyanosis of the face, œdema of the lower extremities, &c.

Death, primarily due to respiratory failure, is often preceded by
general twitchings or convulsions.

The whole course of the illness seldom lasts more than a week, the more
acute cases terminating within two or three days.


=Treatment.= Whether threatening, developing, or obviously present, the
patient should be treated with urotropin (see p. 116). In its early
stages of development immediate operation affords some hope of cure,
such treatment having as its basis the supply of adequate drainage. The
source of the infection must be removed--so far as circumstances
permit--the dura mater freely incised, and the pia-arachnoid region so
opened up as to allow of the escape of some of the purulent or
semi-purulent fluid. The wound is largely allowed to remain open, packed
with gauze. The predominant organism may be isolated and, if time
allows, suitable vaccine treatment instituted. In the meantime, 20 to 40
cc. of pyogenes serum should be administered.

From the point of view of diagnosis, _lumbar puncture_ should never be
omitted. The fluid escapes at high tension, is turbid and contains many
polymorphonuclear leucocytes and organisms, the latter verified with the
greatest advantage after centrifugalization. Repeated lumbar punctures
are also said to be of some benefit with respect to _treatment_.


SINUS THROMBOSIS


=Lateral sinus thrombosis.= Soon after entering on its course across the
mastoid process the lateral sinus presents a well-marked S-shaped curve.
This sigmoid sinus bulges markedly forwards--especially on the right
side--towards the region of the mastoid cells and antrum, so much so
that a mere shell of bone intervenes between the sinus on the one hand
and the antral region on the other. Indeed, the relations are so
intimate that one would expect a more frequent occurrence of lateral
sinus thrombosis. Furthermore, the sinus receives numerous venous
communications from the mastoid cells, antrum, and other parts of the
temporal bone, conspicuous amongst the last-named group of vessels being
the mastoid emissary vein which, passing inwards at the upper and
posterior border of the mastoid process, connects the posterior
auricular and occipital veins with the lateral sinus.

From these considerations it is obvious that any acute or chronic
infective process originating either in the aural region or in the
neighbourhood can readily infect the sinus by direct propagation of
organisms along one or more of these inter-communicating vessels
(thrombo-phlebitis).

The sinus may also become infected in middle-ear disease by the more
gradual process of mining and sapping, the osseous barrier between the
antrum and sinus being progressively destroyed by the backward progress
of the aural disease. The sinus may erect an additional barrier by
throwing out granulations (external pachymeningitis) against the
invading host, but, in the event of the attack overcoming the defence,
sinus thrombosis may result, at first perhaps of a non-infective type
but soon becoming definitely septic, the clot softening and
disintegrating (osteo-phlebitis).

There can be no question that middle-ear disease is responsible for the
very great majority of cases of lateral sinus thrombosis, and whether
the infection takes place by extension of thrombus along the connecting
veins (thrombo-phlebitis), or after destruction of the osseous barrier
(osteo-thrombosis), the results are more or less identical.

Thrombosis first occurs in that part of the sinus which is in closest
relation to the primary cause of the infection, the clot rapidly
increasing in size until the lumen of the sinus is entirely obliterated.
In its early stages the thrombus is of a chocolate colour, softening at
a later date and breaking down into a purulent material. Many varieties
of bacteria may be present though the infection is mainly dependent on
the presence of the streptococcus pyogenes.

Two changes may now occur:--(1) the central portion of the thrombus,
having softened into a purulent material, may be limited by the firmer
thrombus in front and behind; and (2) the thrombus may extend into the
neighbouring and connecting venous channels _downwards_ along the course
of the internal jugular vein, _backwards_ along the course of the
lateral sinus, _inwards_ along the course of the superior petrosal
sinus, _outwards_ along the line of the mastoid emissary vein,
_downwards_ through the posterior condyloid foramen, and _inwards_ along
meningeal veins.

The =symptomatology= may be considered as follows:--

(1) Symptoms dependent on the extension of the thrombus to neighbouring
venous and lymphatic channels.

(2) Symptoms resulting from toxic absorption or dependent on the
transmission of infected material to other parts of the body.

1. _Symptoms dependent on the extension of the thrombus to neighbouring
venous and lymphatic channels._ When the thrombus spreads downwards
along the course of the _internal jugular vein_, there is swelling and
tenderness along the line of the vein. The vessel, though thrombosed in
its upper part--perhaps throughout its whole extent--is itself seldom
palpable, the cervical swelling usually being dependent on associated
lymphadenitis and lymphangitis. In those few cases where the thrombosed
vein can be felt, resembling a ‘buried lead pencil’, the thrombus is
sometimes of the non-infective type.

The combined venous and lymphatic involvement causes œdema of the
tissues, pain, and rigidity on attempted movement. The anterior and
external jugular veins may become engorged from the extra strain thrown
upon them. Subsequently, the inflamed parts may break down and extensive
cervical suppuration result.

When the thrombus spreads _backwards_ along the course of the _lateral
sinus_, the coagulation process may extend as far as the torcula and
even further. Evidence as to the nature and extent of the process is not
always apparent, though one expects to find some œdema of the overlying
scalp tissues.

When the process spreads _inwards_ along the course of the _superior
petrosal sinus_ there is considerable risk of involvement of the
corresponding cavernous sinus, possibly of the opposite sinus also (see
p. 288).

When the process spreads _outwards_ along the course of the _mastoid
emissary vein_, œdema, and dilatation of veins in the post-auricular
region are observed, associated with tenderness on palpation. This is
most apparent at the upper and posterior border of the mastoid process.

When the thrombus spreads _downwards_ along the course of the _posterior
condyloid vein_, there may be some œdema and pain on pressure in the
upper part of the posterior triangle of the neck, associated with
glandular enlargement in the region. These symptoms are dependent on the
connexion established by the posterior condyloid vein between the
sigmoid sinus and the deep veins of the neck.

When the thrombus extends _inwards_ along the meningeal veins,
meningitis, meningo-cerebritis, and cerebral abscess result.

2. _Symptoms resulting from toxic absorption or dependent on the
transmission of infected material to other parts of the body._

_Optic neuritis_ is present, according to Hunter Tod, in about 50 per
cent. cases. It develops rapidly and attains a high degree of intensity.

_Headache_ is usually intense in character, persistent, but little
remedied by drugs and presenting marked exacerbations. It is often most
acute over the affected region.

The _mental condition_ of the patient is subject to variation. In the
average case mental symptoms are quite disproportionate to the severity
of the disease. Sometimes the patient is cheerful, perhaps rather
excited, retaining his faculties to the last, in other cases--as the
result of excessive toxic poisoning--he lies in a stuporose,
typhoid-like state. When the thrombus is associated with meningitis,
meningeal symptoms predominate.

_Vomiting_ is often a conspicuous feature, generally of the so-called
‘cerebral’ type, a regurgitation without nausea and retching.

The _pulse_ is rapid, the rhythm irregular, and the tension lowered.

The _temperature_. The formation of the thrombus is usually notified by
the advent of one or more severe rigors, the temperature rising to 103°
or more. During the height of the illness the temperature is high but
remittent, and rigors are frequent. The occurrence of a series of rigors
is almost certainly indicative of sinus thrombosis. Any marked remission
of temperature is succeeded by profuse sweating, but, with this
exception, the skin remains dry and burning.

Each rigor implies the extension of the thrombus to other venous
channels or the transference of infected particles, by means of the
blood-stream, to other parts of the body. In the young general
convulsions are often observed.

The tongue is brown and dry, the breath foul and diarrhœa of common
occurrence. The skin may be jaundiced, and septic rashes are prone to
develop. The liver and spleen may be enlarged and tender. Cough and foul
sputum point to pulmonary infarction.


=Treatment.= The mastoid antrum is rapidly exposed and the conditions
investigated. The bone is then chiselled away in the backward direction,
with the hammer and gouge, so as to expose the lateral sinus. The
question then arises as to the condition of the sinus. This is a matter
that may require considerable experience. The surgeon should be guided,
not so much by exploratory puncture as by the surroundings and general
appearance of the sinus. Thus, the absence of bleeding from the mastoid
emissary vein during the process of exposure is very significant of
sinus thrombosis. Again, whilst the normal sinus pulsates, is of dark
blue colour and presents a shining surface, the thrombosed channel may
be covered with pale granulations or obscured by fibrinous deposit, it
does not pulsate, and appears of a yellow or deep purple colour. Between
it and the bone there may be a collection of purulent matter. In the
event of doubt, the surrounding regions should be carefully protected
with gauze, after which the sinus may be punctured with a needle. The
absence of fluid blood is conclusive of thrombosis.

[Illustration: FIG. 85A. DIAGRAM TO SHOW THE USUAL POINTS AT WHICH THE
LATERAL SINUS IS PRIMARILY INFECTED. A, High up; from the posterior
mastoid cells. In this case it may not be necessary to tie the jugular
vein. B, Low down; involving the jugular bulb. This necessitates
ligature of the vein. (After Hunter Tod.)]

[Illustration: FIG. 85B. THE LATERAL SINUS EXPOSED AND OPENED. The lumen
of the sinus is obliterated above and below the region of the infected
thrombus by plugs of ribbon gauze pressed in between the sinus wall and
the overlying bone. In this case it is not necessary to tie the jugular
vein. (After Hunter Tod.)]

In the event of the surgeon concluding that thrombosis is present,
subsequent procedures vary according to the extent of the thrombus.
Thus, _when the clot appears to terminate above the jugular bulb_, a
strip of gauze is inserted between the bone and the parietal wall of the
sinus so as to obliterate the lumen of the sinus on the cardiac side of
the clot.

The danger of further extension of the clot being thus obviated, the
bone is nibbled away in the backward direction till at least half an
inch of healthy vessel is exposed on the occipital side of the thrombus.
A second gauze plug is then introduced so as to obliterate the sinus
lumen in that region also.

In the interval between the two plugs the sinus is freely laid open, all
clot and granulations being gently curetted and washed away. Some
bleeding may take place during these procedures, from the mouths of
certain vessels entering the sinus between the two compressed regions.
This is in itself a favourable symptom, insomuch as it proves that the
thrombotic process has not extended in those directions. This hæmorrhage
may be controlled with gauze plugs. The parietal sinus wall in direct
relation to the thrombus is freely cut away, after which the whole field
is lightly packed with gauze and the ear sewn back into position. The
main portion of the wound is left open, the sinus plugs being brought to
the surface whilst those inserted into the combined middle ear and
antrum emerge from the external auditory meatus.

All gauze-plugs may be withdrawn after twenty-four to thirty-six hours,
the wound cleansed and lightly repacked. This process is continued daily
till all is healed.

_When the clot extends into the jugular bulb, and when the jugular vein
appears to be involved_, it is necessary to expose and ligature the vein
in the neck, thus preventing further extension of coagulation and
diminishing the risk of general infection. This measure should be
carried out before the lateral sinus is laid open. With fresh gloves and
another set of instruments, the vein is exposed so as to allow the
application of two ligatures, and the division of the vessel between
those two ligatures. If possible, the ligatures should be applied above
the level of the entrance of the common facial vein. In all cases,
however, the application must be carried out, if possible, below the
lower limit of the thrombus. After the vein has been divided, the upper
end may be dissected in such a manner as to allow of its being brought
to the surface of the wound and there anchored.

Elsewhere the neck-incision is sewn up and protected with collodion
gauze. The surgeon then returns to the mastoid and sinus regions,
completing the exposure of the sinus and laying it open freely to the
surface. At the termination of these procedures, an attempt may be made,
by irrigation between the open sinus above and jugular vein below, to
wash away all thrombus contained in the intervening portion of the
vessel.

Finally, both sinus and aural regions are packed with gauze, in a manner
similar to that described above. Dressings are reapplied as
circumstances demand, and the wounds allowed to heal by granulation.

The great frequency of a streptococcus pyogenes infection justifies one
in the early administration of anti-streptococcic serum (20 to 40 c.c.
of Burroughs Wellcome’s ‘Pyogenes’) followed by an autogenous vaccine as
soon as that can be prepared.

MAIN POINTS IN THE DIFFERENTIAL DIAGNOSIS BETWEEN

  ---------------+-----------------+-----------------+------------------
                 |  BRAIN ABSCESS  |   MENINGITIS    |  LATERAL SINUS
                 |                 |                 |   THROMBOSIS
  ---------------+-----------------+-----------------+------------------
  _Onset_        |   Insidious.    |     Acute.      |      Acute.
                 |                 |                 |
  _Temperature_  |Subnormal (see p.|First a rigor,   |First a rigor,
                 |255).            |then high and    |then high and
                 |                 |continuous       |continuous
                 |                 |temperature,     |temperature,
                 |                 |usually          |usually remittent.
                 |                 |intermittent.    |Frequent rigors.
                 |                 |                 |
  _Pulse_        |Slow (see p.     |    Rapid.       |     Rapid.
                 |255).            |                 |
                 |                 |                 |
  _Mental        |Often apathetic. |Very restless and|In the early
  condition_     |In the later     |delirious.       |stages, the mind
                 |stages, stupor   |Sometimes        |is clear. This
                 |and loss of      |maniacal. Coma   |condition may
                 |consciousness.   |towards the end. |persist till near
                 |                 |                 |the end when
                 |                 |                 |delirium and coma
                 |                 |                 |become evident.
                 |                 |                 |
  _Special       |Paresis or       |Squints,         |Œdema over
  symptoms_      |paralysis,       |retraction of the|mastoid, pain
                 |according to the |head and neck.   |along course of
                 |site of the      |Irregular        |internal jugular
                 |lesion.          |palsies.         |vein. Enlarged
                 |                 |                 |cervical glands.
                 |                 |                 |
  _Blood and     |Progressive      |Increased        |Blood infection
  cerebro-spinal |leucocytosis.    |leucocyte count  |frequent.
  examination_   |Increased        |and organisms in |
                 |leucocytes in    |fluid withdrawn  |
                 |cerebro-spinal   |by lumbar        |
                 |fluid.           |puncture.        |
  ---------------+-----------------+-----------------+------------------

In typical cases no great difficulty will be experienced in diagnosing
between brain abscess, meningitis, and lateral sinus thrombosis. In many
cases, however, two or more of these conditions may be co-existent.
Thus, both brain abscess and lateral sinus thrombosis are often
complicated by the presence of a meningeal infection. Again, the undue
prominence of abdominal, cardiac, or pulmonary symptoms--more especially
in cases of lateral sinus thrombosis--demand the full consideration of
enteric fever, endocarditis, and pneumonia. Thus, in a case recently
under my care at the hospital, and in which I had the benefit of the
wide experience of my Aural colleague, Mr. West, operative procedures
were carried out on the mastoid region, the patient dying some days
later from enteric fever. Again, the question of differential diagnosis
between tuberculous meningitis, brain tumour and brain abscess is always
cropping up. Thus, a short time ago, I explored both temporo-sphenoidal
lobes in a boy suffering from double otitis media and presenting
well-marked general cerebral symptoms, only to find that he was a
subject of tuberculous meningitis.

The diagnosis is often difficult, and no trouble must be spared in the
complete investigation of the case. _Lumbar puncture_ should invariably
be carried out, the fluid being examined both cytologically and
bacteriologically. In all cases of doubt one would be wise to call in
further advice before undertaking exploratory operation.


=Cavernous sinus thrombosis.= Thrombosis of the cavernous sinus arises
either as an osteo-phlebitis or as a thrombo-phlebitis. In the former
case, the thrombus is dependent on disease of the bones related to the
sinus--arising more especially as the result of prolonged sphenoidal
sinusitis--whilst, in the latter instance, the sinus becomes infected
through one of the many vascular communications connecting it with other
neighbouring regions. Thus the radicles of the ophthalmic vein, by means
of their communication with orbital, ethmoidal, and upper nasal vessels,
and their connexion at the inner canthus of the eye with radicles of the
angular vein, afford the most ready means of infection. Again, infection
may spread from the auditory region along the superior petrosal sinus,
and from the tonsillar and pharyngeal regions along the various emissary
veins connecting the cavernous sinus on the one hand with the deep
cervical vascular system on the other.

The two cavernous sinuses intercommunicate by means of the circular
sinus, and consequently thrombosis of the one sinus is liable to involve
its fellow. According to Macewen,[57] bilateral trouble occurs in 50 per
cent. cases, the infection often spreading from one sinus to the other
within twenty-four to thirty-six hours.

Thrombosis of the cavernous sinus is often associated with meningeal
infection or brain-abscess.


=Symptomatology.= (_a_) _Symptoms dependent on the formation of the
thrombus and its extension to neighbouring venous and lymphatic
channels._ The presence of the thrombus and its extension into
ophthalmic, angular, and retinal veins leads to proptosis, paresis of
the ocular muscles, disturbances of vision, and œdema. _Proptosis_ is of
rapid development, frequently reaching its maximum within a few hours,
the globe being protruded in the downward and outward direction. With
respect to _ocular palsies_, the movements of the globe are greatly
restricted with squints, ptosis, and perhaps complete ophthalmoplegia.
The pupil may be contracted during the earlier stages, becoming fully
dilated and insensitive at a later date. The _vision_ suffers in
proportion to the degree of paralysis of ocular muscles and associated
retinal hæmorrhages and thrombosis. The veins of the lids, conjunctivæ,
and upper part of the face and forehead are engorged, with corresponding
œdema of the soft parts. The conjunctivæ may be chemotic.

The spread of the thrombus to the opposite sinus results in the
development of bilateral symptoms, whilst the involvement of the
petrosal sinus may bring about thrombosis of the lateral and sigmoid
sinuses, with corresponding developments.

In other cases the meningeal veins are affected at an early date, in
which case the symptoms dependent on the cavernous thrombus are obscured
by those resulting from the meningeal infection.


(_b_) _Symptoms dependent on toxic absorption or resulting from the
transference of infected particles to other parts of the body._ These
more general symptoms closely resemble those enumerated when discussing
lateral sinus thrombosis (see p. 283). Headache, however, is of the most
intense type, and pain, of a severe neuralgic character, is referred
along the course and distribution of the first and second divisions of
the fifth nerve.


=Treatment.= It has been suggested that exploration could be carried
out, the thrombus evacuated, and the cavernous sinus region drained from
the naso-ethmoidal region or by approach along the floor of the middle
fossa of the skull--an exaggerated Gasserian ganglion operation. Both
these methods have been tried, but the difficulties encountered and the
want of success tended to show that cavernous sinus thrombosis was
beyond the reach of the surgeon. However, of recent date, more hopeful
views have been entertained, it being suggested that the globe should be
removed, the sinus explored, and the orbital cavity packed with gauze.
It is doubtful, however, whether the end justifies the means.


=The prognosis in brain abscess, meningitis, and sinus thrombosis.= A
patient may be expected to recover from _brain abscess_, whether
temporo-sphenoidal, cerebellar, or frontal, if an early diagnosis be
made, if the case be uncomplicated by meningeal infection or sinus
thrombosis, and if the evacuation be carried out without any great
difficulty. As Sir William Macewen[58] pointed out, ‘an uncomplicated
brain abscess may be regarded as the most hopeful of all cerebral
affections.’ In fatal cases, death results from general meningeal
infection or from the bursting of the abscess into the lateral
ventricles.

In _meningitis_ the prognosis is bad, more especially when the process
is widespread. Early exposure of the affected region and the supply of
adequate drainage offer the only hope of recovery. This, even under the
most favourable circumstances, is a desperate remedy.

The prognosis in _lateral sinus thrombosis_ hinges to a large extent on
the time at which operative procedures are carried out. When the case is
seen and operated on at an early date in the history of the disease,
recovery may be anticipated in about 50 per cent. cases. Hunter Tod
states that, when all cases are considered of whatever grade, about
one-third recover. Death results from pyæmia, septicæmia, meningitis, or
brain abscess.

_Cavernous sinus thrombosis_ of the infective variety almost necessarily
terminates fatally. Death results from causes similar to those observed
in cases of lateral sinus thrombosis.


HERNIA CEREBRI

The term Hernia cerebri was formerly used as inclusive of all those
conditions in which the brain protruded through some aperture in the
skull, whether such opening was congenital, traumatic, or
post-operative.

Owing to the recent advances in cranio-cerebral surgery, especially with
reference to the frequent adoption of decompression operations, it is
advisable that the cases should be classified into two groups:--

=1. Cases of hernial protrusion=, including cephaloceles (see Chapter
I), protrusions intentionally produced by the surgeon in a decompression
operation, and those which follow after unsuccessful operations for
tumour removal. It will be observed that, in all these cases, the
projecting brain, though bulging through its osseous barrier, is still
protected by a more or less normal scalp-covering.

=2. Cases of hernia cerebri.= Here, as the result of injury to scalp,
bone, dura, and brain, the cerebral substance bulges through a
deficiency in the vault and presents on the surface, uncovered by
integument. Hernia cerebri _can_ develop under non-infective conditions,
the congested state of the bruised or lacerated brain bringing about
that degree of intracranial tension which can only be relieved by the
outward projection of the brain. Still it must be accepted that Hernia
cerebri almost invariably implies some bacterial infection.

_Hernial protrusions_ are dealt with elsewhere. _Hernia cerebri_
requires some consideration. Its development, by reason of its usual
bacterial agency, must always be regarded as of serious import. The
congested brain bulges through the aperture in the skull and presents on
the surface as a purple--sometimes black--fungating mass, bleeding
freely, and associated with a considerable discharge of cerebro-spinal
fluid, serum, and pus.

The effects produced by this condition vary according to the extent of
the cerebritis, and the question of associated meningeal infection.

When associated with meningitis those symptoms which might result from
the hernial protrusion are more or less obscured by those dependent on
the meningeal infection. Under other circumstances, the symptoms vary
according to the extent and position of the area involved. Thus, when
the infection is limited to the surface of the brain in the immediate
vicinity of the aperture in the bone, the patient may merely complain of
some headache and present some symptoms of cerebral irritation. More
usually, the infection spreads rapidly to the surrounding brain
substance, and the patient evidences the most acute stage of cerebral
irritation, passing thence rapidly into a stuporose, typhoid-like
condition.

[Illustration: A

FIG. 86. A CASE OF HERNIA CEREBRI. A, The abscess after removal (natural
size), cut so as to show the thickness of capsule.]


=Treatment.= With the object of reducing the infectivity of the
protruding brain, fomentations have been advocated. From my own
experience, however, it would appear that their application tends to
increase the degree of protrusion, and that better results may be
obtained by keeping the exposed brain as dry as possible, painting over
with a 2¹⁄₂ per cent. solution of iodine in rectified spirit, dusting
with antiseptic powder, and protecting with dry dressings, frequently
replaced.

In the event of failure to improve the condition by means of these minor
remedies--a too-frequent occurrence--excision of the protruding mass may
be regarded as a perfectly justifiable procedure, providing that the
hernia does not include the cerebellum or motor cortical region. The
protrusion is shaved away flush with the level of the skull, the raw
surface of the brain lightly painted with iodine, dusted with iodoform
or other antiseptic powder, and protected with gauze and wool.

The prognosis is necessarily most grave, but the most astounding
recoveries have taken place under this mode of treatment.

[52] _Archiv für Ohrenheilkunde_, vol. xxix, p. 17.

[53] _Diseases of the Ear_, Oxford Medical Publications, p. 257.

[54] _Pyogenic Diseases of the Brain and Spinal Cord._

[55] _Some Points in the Surgery of the Brain_, p. 95.

[56] Macewen, _Pyogenic Diseases of the Brain and Spinal Cord_.

[57] _Pyogenic Diseases of the Brain and Spinal Cord_, p. 247.

[58] _Pyogenic Diseases of the Brain and Spinal Cord._




CHAPTER IX

BULLET-WOUNDS OF THE SKULL AND BRAIN


In the consideration of bullet-wounds of the skull and brain the
following factors must be taken into account:--

The velocity of the bullet.

The distance at which the bullet is fired.

The size of the bullet.

The nature of the bullet.

The angle of impact.

The position of the bullet at the moment of impact.

Before, however, noting the varying effects on the skull as produced by
one or more of these factors, it will be necessary to allude briefly to
the average effect on the skull as produced by bullet-wounds in general.

‘When a foreign body passes through any part of the skull--it matters
not what the direction may be--the aperture of exit is always greater
than the aperture of entry.’ Such was the law enunciated by Teevan in
1864. The explanation is as follows: ‘The aperture of entry is caused by
the penetrating body only, whilst the aperture of exit is larger,
insomuch as it is made by the penetrating body plus the fragments of
bone driven out of the proximal table and diploe.’ It might also be
added that the greater degree of damage will always be incurred by the
unsupported table--the internal at the wound of entry, the external at
that of exit.

The size and shape of the aperture of entry through the external table
bears a close resemblance to the size and shape of the entering bullet.
As a general rule, it is round or oval, and presents clean-cut edges
with some small radiating fissures. The aperture of entry through the
internal table is larger, the margins inverted towards the brain, the
radiating fissures more pronounced, and small fragments of bone
in-driven towards the brain.

In the event of perforation of the skull through the medium of a
high-velocity bullet, the aperture of exit through the internal table
closely resembles that through the external table at the site of entry,
with the exception that it is influenced by any changes in position that
the bullet may have undergone during its transmission through the brain.
The wound of exit through the external table is again greater than that
through the internal--in accordance with Teevan’s law--the margins
everted, the surrounding bone fissured or comminuted, whilst fragments
of bone may be driven out beneath the lacerated scalp, or even blown
completely away. On the other hand, when the bullet is fired at close
range, the aperture of exit is often considerably larger than that of
entry--due, in all probability, to superadded explosive effect.

The effect of the _velocity_ of the bullet on the fracture:--The greater
the velocity of the bullet the greater the resemblance of the wounds of
entry and exit to the size and shape of the bullet, the ‘cleaner’ the
holes, and vice versa.

The effect of _distance_:--When the bullet is fired from a distance, but
with full effect, the hole is clean cut and presents the characteristics
enumerated above. When the bullet is ‘spent’, the osseous injury at the
point of impact is usually of a more extensive character than when the
bullet possesses a higher degree of velocity. When fired at close
quarters the damage incurred from the impact of the bullet is increased
by the force of the forwardly driven air and gas. The skull suffers
proportionately, the scalp being severely lacerated, burnt, and
circumferentially ingrained with powder, the bone extensively
comminuted, and the brain severely lacerated.

The effect of _size and shape_ of the bullet:--The effects produced on
the skull in relation to the size and shapes of the bullet are so
obvious as to require no description. The nature of the bullet must also
be taken into consideration, whether of the soft-nosed variety,
expansile, &c.

The effect of the _angle of impact_:--The lesion produced by the bullet
varies according as to whether the bullet glances across the vault or
strikes the bone at right angles. In the former case a ‘gutter’ fracture
may result, varying in degree and associated brain complication
according to the angle of impact. In the latter case the skull is
penetrated or perforated.

The effect of the _position of the bullet_ at the moment of
impact:--The bullet, at the moment of impact, may be so changed in
position--head-over-heels, ricochet, &c.--that the skull may be struck
by its long axis instead of by its nose. In such cases, the wound of
entry will be more extensive than under ordinary circumstances.

It is obvious, therefore, that many factors require consideration in
estimating the extent of the osseous lesion and the nature of the
complications existent in any given case. Due allowance must also be
paid to other factors entering into the case, more especially in
relation to the weapon used--pistol, revolver, gun, &c.


=Injury to the bone.= The various injuries to bone may be classified as
follows:--

Fractures limited to the external table.

Fractures limited to the internal table.

Gutter fractures.

The complete fractures produced by a penetrating wound.

The complete fractures produced by a perforating wound.


=Fractures limited to the external table.= Fractures of this nature are
of exceedingly rare occurrence. They are produced by a bullet which
strikes the skull in such an oblique direction that the scalp and
external table are torn away (‘gutter’ fractures), or by a bullet which,
directed against the outer wall of the frontal sinus, possesses
sufficient force to comminute the outer wall of that sinus, but, from
loss of momentum, is incapable of penetrating further.


=Fractures limited to the internal table.= These fractures are even more
rare than those described above. Their occurrence is probably only
possible when the bullet strikes the skull in a markedly oblique
direction, and with greatly diminished velocity--‘spent’ bullets. I
believe I am correct in stating that only one instance of this
particular variety of fracture was observed in the South African War. In
any case, they are of such infrequent occurrence that they may be
practically disregarded.


=Gutter fractures.= Gutter fractures are almost invariably dependent on
the impact of a glancing bullet. They may be arranged in three groups,
according to the extent of the osseous lesion.

1. Where the external table is blown away, leaving the internal table
exposed, perhaps comminuted.

2. Where the internal table is driven in the inward direction, pressing
on, irritating, and perhaps lacerating the dura mater.

3. Where the whole thickness of the bone is blown away, leaving a gaping
wound from which brain-matter may protrude.

[Illustration: FIG. 87. DIAGRAMMATIC ILLUSTRATION OF THE THREE FORMS OF
‘GUTTER’ FRACTURE. (For further description, see text.)]


=The complete fractures produced by penetrating and perforating wounds.=
The general effects as produced by penetrating and perforating
bullet-wounds of the skull and brain are depicted in Fig. 88, and
described in the text associated with that figure.


=Injury to the brain.= Brain lesions vary ‘from a single track with
small points of extravasation in neighbouring areas to a condition of
hæmorrhagic pulp, which latter condition is the result of injury from
the projectile associated with bleeding, often extensive, into
neighbouring areas, disintegrating and pulping the brain-substance.
These latter cases are generally fatal, and are accompanied not
infrequently with meningeal and ventricular hæmorrhage’ (Bowlby).[59]

The worst degrees of brain-injury arise when the injury is inflicted at
close range, more especially at the site of emergence of a perforating
bullet, the damage to the soft parts being there magnified by the waves
and vibrations set up by the bullet during its passage across the brain.
In many cases also the brain is dashed as a whole against the opposing
osseous barrier (laceration by contre-coup).

The general effects produced on the skull and brain by a perforating
bullet of high velocity are shown in Fig. 88.


=Symptomatology.= It is unnecessary to enter into details with regard to
the symptoms arising from bullet-wounds of the skull and brain, for they
closely resemble those previously enumerated in the chapters dealing
with fractures of the skull and injury to the brain. There are, however,
a few special points to which attention should be directed.

1. External hæmorrhages are seldom profuse.

2. The escape of cerebro-spinal fluid is of infrequent occurrence,
probably due to the fact that the apertures of entry and exit are
blocked up with scalp, fragments of bone, and pulped and swollen brain.

3. Concussion and irritation are prominent symptoms, compression is
rarely seen in its typical form. As Spencer[60] says, ‘The dominant
feature is usually concussion. The extent of the paralysis depends on
the region injured, and there is often at first extensive temporary
paralysis from vibratory concussion of the brain substance suspending
its functions over a wide area around the bullet-track.’ Cerebral
irritation and Jacksonian fits are frequently observed.


=Indications for operation.= There is a great uniformity of opinion with
regard to the indications for operation as expressed by those who have
had considerable experience in wounds of this nature. One has only to
glance through the works of recognized authorities--Spencer,[61]
Bowlby,[62] Makins,[63] Lawford Knaggs,[64] &c.--to see that it is an
accepted rule that all bullet-wounds of the skull and brain call for
early operative interference, it being granted that the condition of the
patient is compatible with such treatment.


=Operation.= The operative details may be considered under two
headings:--

(_a_) The exploration of the wounds of entry and exit.

(_b_) The search for and removal of the bullet.

[Illustration: FIG. 88. TO ILLUSTRATE THE EFFECTS PRODUCED BY A
PERFORATING BULLET-WOUND. 1, The inverted scalp at wound of entry; 2,
Subaponeurotic hæmorrhage; 3, The wound of entry into the skull; 4,
Extra-dural hæmorrhage; 5, Lacerated dura mater; 6, Subdural hæmorrhage;
7, In-driven fragments of bone; 8, The passage through the
brain-substance; 9, Ventricular hæmorrhage; 10, The wound of exit
through the brain; 11, Subdural hæmorrhage; 12, The wound of exit
through the dura mater; 13, The wound of exit through the skull; 14, The
wound of exit through the scalp.]

_The exploration of the wounds of entry and exit._ Whether the skull be
penetrated or perforated, the wounds are investigated after similar
general principles. After careful shaving and cleansing of the whole
scalp, and after application of the scalp-tourniquet, a scalp-flap is
turned down, the centre corresponding as far as possible to the site of
entrance or emergence of the bullet. The under aspect of the flap is
examined for loose fragments of bone, hair, portions of headgear, &c.
These are removed and the flap cleansed. The bone is next examined. All
loose fragments are removed, both large and small. The smaller are
discarded, the larger are boiled (for ten minutes) and preserved in hot
saline solution for replacement at the termination of the operation, if
such a course should be deemed advisable (see p. 132). Those fragments
of bone which retain their pericranial attachments are merely elevated
and turned aside, to be again placed in position at the proper time.

Trephining is seldom necessary, the hole in the bone usually allowing of
the application of craniectomy forceps, if any enlargement should be
requisite.

A good view of the dura mater can now be obtained. If that membrane be
merely punctured or incised, the tear must be enlarged with
blunt-pointed scissors so as to allow of complete examination of the
underlying brain. Hæmorrhage from meningeal vessels is controlled by the
application of ligatures to all vessels that cross the line of dural
section.

The lacerated brain is _gently_ irrigated with saline solution (at a
temperature between 110° and 115° Fahrenheit), and all blood and pulped
brain matter washed away. The cortex is then lightly examined with the
finger and probe for any fragments of bone that may be embedded in the
brain substance. The removal of such fragments should be conducted with
all possible gentleness. The surgeon should be satisfied that no foreign
body remains. The bullet, when encountered, is removed. Needless to say,
the presence of a bullet and the existence of in-driven fragments of
bone should be investigated previous to the adoption of operative
measures by means of X-ray photography.

If the brain be penetrated or perforated a drainage tube is introduced
through scalp-flap and dura mater in such a manner that its distal end
lies in relation to the track through the brain or flush with its
lacerated surface. Elsewhere the dura is sewn up (fine catgut sutures)
and the scalp-flap replaced, the drainage tube being anchored to the
scalp with a single suture. The tube should be allowed to remain _in
situ_ for at least forty-eight hours and longer if necessary, the
surgeon being guided by the amount of discharge and by the general
progress of the case. In all cases of doubt the surgeon should err on
the side of leaving the tube in position for a longer period of time,
merely shortening it daily. Premature removal may lead to disastrous
results. There can be no question that ultimate success hinges to a
large extent on primary or early healing of the wound.


_The search for and removal of the bullet._ In the event of a wound of
entry only, it may be presumed that the bullet is within the skull.
Bullets, however, pursue such unexpected and devious courses within the
skull, and possess such a tendency to gravitate towards the base of the
brain, that no attempt should be made at removal except after full X-ray
investigation, stereoscopic if possible.

To this rule there are two exceptions:--(1) where the bullet lies
superficial in the brain substance, and (2) where there exists, at the
opposite side of the skull, what may be termed an area of attempted
exit, that is to say, an area of bone elevation and blood extravasation,
suggesting that the bullet has penetrated through the brain and impinged
against the opposite side of the skull. In both these instances
operative measures are not only justifiable but often definitely
indicated. On the other hand, it cannot be urged too forcibly that hasty
and ill-determined explorations usually terminate in failure. Even under
the most promising circumstances it by no means follows that the bullet
will be found at the site of counter-trephining, as it may have
rebounded to some more distant region of the brain, necessitating an
operation conducted over a totally different region. Thus, in a case
recently under my care, the bullet entered at the right temporal region,
penetrated the brain and produced on the left side of the head a
well-defined wound of attempted exit. The bullet, however, on striking
the opposing side of the skull rebounded, and was subsequently found in
the apex of the descending cornu of the right lateral ventricle. This
case affords a good example of the uncertain course pursued by bullets
entering the cranial cavity.

However, in certain cases of emergency and in others of expediency an
immediate search should be made for the bullet. The operation should be
carried out with a light hand and not unduly prolonged.

In order to find and remove the bullet various probes and extractors
have been invented. Perhaps the best of these is Sheen’s bullet-forceps,
probe, and telephone-detector.

‘The forceps are so constructed that they may be attached directly to
the telephone-detector and used as a combined probe and forceps, or they
may be used in combination with the specially designed graduated probe
attached to the detector in the following manner: The bullet having been
located with the probe, the forceps are introduced along the probe, the
jaws of the forceps being provided with an oblique groove for this
purpose. In both methods of use the telephone-detector is in
uninterrupted contact with the bullet during extraction, an advantage
which much facilitates the operation, and ensures the least possible
damage of tissue. In cases where the forceps are used as a probe and
forceps combined, the connexion attached to the forceps is composed of
silver wire, which can be readily sterilized, and while of sufficient
rigidity to avoid risk of accidental short-circuiting with the patient’s
body, is flexible enough not to interfere with the delicacy of
manipulation. The telephone-detector is placed on the head of the
operator, and the flat plate on the patient’s body, good contact being
secured by means of a damp roll of lint, or other material, moistened
with a saturated saline solution.’

[Illustration: FIG. 89A. SHEEN’S BULLET-PROBE AND FORCEPS.]

[Illustration: FIG. 89B. SHEEN’S TELEPHONE BULLET-DETECTOR.]

‘The probe is introduced, and when a metallic foreign body is touched a
fall of potential occurs, and the telephone buzzes. It is necessary to
point out that no mistakes can be made, as may be the case with a
battery in circuit. In using the “auto-telephone probe” the body
constitutes an electrolyte, the plate one pole of a voltaic circle, the
probe the other; on touching a metallic body different to that of the
probe, a difference of potential occurs, and the current ensuing flows
through the telephone and is recorded by the diaphragm in the usual
way.’[65]

If the bullet be not found it should be allowed to remain _in situ_ till
such time shall have elapsed as will enable the surgeon to determine
whether further operative measures are indicated, time being allowed
also for skiagraphy and for the evolvement of another plan of campaign.
It is of course a well-known fact that bullets in certain regions of the
brain--e. g. the frontal lobe--may exercise but little effect on the
individual. Further measures are also indicated when the want of
cleanliness of the wound and the anatomical situation of the bullet
demand secondary operative procedures. All remote operations are planned
according to the localizing symptoms, aided by X-ray photography.

After exploration for and removal of the bullet an extensive osseous
defect may remain. Opinions differ with respect to the time at which an
attempt should be made to remedy the deficiency and as to the operative
technique appropriate to the condition. The nature of the wound must
always be taken into consideration, for the application of any plate of
foreign material is doomed to failure in the event of the slightest
degree of suppuration. As a general rule, it may be accepted that it is
advisable to postpone such measures till after the primary or early
healing of the wound. Further delay, however, tends to allow of the
formation of such adhesions as will result in the development of
Jacksonian epilepsy, chronic headache, traumatic insanity, &c. The
operative features requisite to the interposition of plates between the
bone and the scalp, and other measures, are fully detailed in Chapter
VI.

‘The _after treatment_ consists in keeping the patient as quiet as
possible, and the administration of a fluid diet. In some cases,
recurring symptoms pointed to the continued presence of bone fragments;
these were usually indicated by signs of irritation, or often by local
inflammation, in the latter case infection taking the greatest share in
the causation. Such cases needed secondary exploration, and the
wonderful success of this operation, even when the wound was evidently
infected, was perhaps one of the most striking experiences of surgery in
general.’ (Makins.)[66]


=Complications.= The more important early complications are meningitis,
hernia cerebri, and brain abscess. For the Symptomatology and Treatment
of these conditions the reader is referred to Chapter VIII.


=Results.= The prognosis in any given case depends on the degree of bone
and brain injury, on the presence or absence of the bullet in the brain,
and on the ‘cleanliness’ of the wound. In the American Civil War 61·2
per cent. of all fractures of the skull terminated fatally, in the
Franco-German War 51·3 per cent., and in the South African War 33·1 per
cent. This decreasing mortality is undoubtedly dependent on the improved
methods of treatment.

When the injury is inflicted at short range the prognosis is undoubtedly
less favourable. ‘At short range, the characters of the wounds, and the
severity of the symptoms, rendered the immediate prognosis uniformly
bad, a very great majority of the patients dying, and that at the end of
a few hours or days.’ (Makins.)

The best results were obtained when the injury was received in the
frontal region. The occipital region comes second, and the cerebellar
last. Most injuries near the base of the skull were fatal. Longitudinal
wounds were more serious than transverse. However, the most surprising
recoveries were made, both with and without operative treatment.

The prognosis with regard to pistol wounds is absolutely bad. Phelps[67]
records the following results in cases that came under his own
observation.

Death occurred at once or within the first hour in 15 cases.

Death occurred within twelve hours in 7 cases.

Death occurred within fifteen hours to forty days in 10 cases.

Recovery in but 8 cases.

The more remote results are exceedingly difficult to determine, for it
is impossible to obtain an accurate account of the subsequent course of
events in all cases. With regard to the question of the after-history,
Makins[68] writes, ‘I feel certain that a long roll of secondary
troubles from the contraction of the cicatricial tissue, irritation from
distant remaining bone fragments, as well as mental troubles from actual
brain destruction, await record in the near future.’ In the experience
of the writer, this statement is fully justified. The hospital surgeon
continually meets with cases exemplifying the more remote effects,
varying from slight lesions associated with chronic headache to others
showing considerable deficiency in the vault of the skull with cortical
degeneration.

Some of these cases are still capable of being cured, others are
hopelessly inoperable.

In the consideration of the more remote results, it must be remembered
that the surgeon comes mainly into communication with those cases which
require further treatment. The more favourable are lost to view. Hence
the difficulty in estimating with certainty the absolute results
obtained after lesions of this nature.

[59] _A Civilian War Hospital._

[60] _Gunshot Wounds_, p. 170.

[61] _Gunshot Wounds._

[62] _A Civilian War Hospital_, p. 228.

[63] _Surgical Experiences in South Africa_, p. 293.

[64] _Lancet_, March 3, 1906.

[65] _Army Med. Corps Journal_, April 1905.

[66] _Surgical Experiences in South Africa._

[67] _Traumatic Injuries of the Brain_, p. 387.

[68] _Surgical Experiences in South Africa._




CHAPTER X

TRIGEMINAL NEURALGIA


Neuralgia of the fifth or trigeminal nerve is, in its varying degrees,
of frequent occurrence. In its cause, manifestations, and progress, it
offers so wide a field for discussion that the question must be focussed
down by means of some simple form of classification such as enables one
to include the majority of cases that come before one’s observation.

For all practical purposes, the following types will be sufficiently
inclusive:--

Neuralgia minor.

Neuralgia major.

Hysterical neuralgia.


NEURALGIA MINOR

This variety is almost invariably dependent in its development on some
exciting cause. In some cases this cause is readily demonstrated, in
others great difficulty may be experienced before the source is
discovered.

These secondary neuralgias may be regarded as resulting from the
following injuries and diseases.

  Diseases of the tongue, fauces, and pharynx. For example, the pain
  referred to the lingual nerve in epithelioma of the tongue.

  Diseases and injuries of the maxillæ. For example, the neuralgia
  associated with dental caries.

  Injuries and diseases of the nose and its accessory cavities. For
  example, the infra-orbital pain experienced in empyema of the antrum.

  Injuries and diseases of the bones of the skull. For example, the pain
  referred along the course of those nerves emerging through the basal
  foramina involved in a fracture of the base of the skull.

  Errors of refraction. For example, neuralgia of the supra-orbital
  nerve.

  Anæmia, influenza, alcoholism, Bright’s disease, cold, worry, malaria
  (brow-ague), rheumatism, &c.

But slight allusion need be made to the _symptomatology_ of neuralgia
minor--the conditions are more or less familiar to every one. The pain,
though usually most intense in that particular branch of the nerve which
is most intimately related to the source of the neuralgia, is often
referred to other branches of the same nerve-trunk, and sometimes to an
entirely different nerve. Thus, in the case of an epithelioma of the
tongue, the pain, though perhaps most acute in the region supplied by
the lingual nerve, is nevertheless frequently referred to the ear along
the course and distribution of the chorda tympani.

The pain is more or less continuous, often associated with
exacerbations, but seldom paroxysmal. The patient frequently complains
of heat and tenderness over the areas supplied by the nerve in question
and, in almost every instance, there are points of special tenderness
corresponding as a rule to the emergence of the nerve-trunk through some
osseous foramen. Again, some relief may be obtained by the application
of pressure over the site of that foramen. For example, neuralgia
dependent on antral empyema is most acute in the region of the
infra-orbital foramen, and relief may be experienced by pressure applied
over that foramen.

In the event of failure to discover an exciting cause, some difficulty
may be experienced in coming to a correct conclusion as to whether the
case belongs to the minor types of neuralgia, or should be relegated to
the more serious group of neuralgia major (tic doloreux). In general,
however, the neuralgias minor may be distinguished from the major
variety by the following features:--

(1) The presence of some detectable forms of nerve-irritation. In the
neuralgias major there may be no such cause.

(2) The relief of symptoms on the successful treatment of the cause.

(3) The relative absence of those paroxysmal attacks which are so
typical of neuralgia major.

(4) The infrequence of severe vaso-motor, trophic, and sensory changes
in the regions supplied by the nerve affected. Such changes are more or
less constant in neuralgia major.

(5) The wide distribution of the pain and its reference to other nerves,
with no clear line of demarcation from neighbouring areas supplied by
totally different nerves. In neuralgia major the pain, though often
involving both second and third divisions of the fifth nerve, is
referred to the areas supplied by those nerves only, with a clear line
of demarcation from neighbouring regions.

In cases of neuralgia of doubtful origin one can only observe the effect
of treatment and be guided by the results obtained.


=Treatment.= The source of the neuralgia requires primary consideration.
When this has been rectified the patient should be treated after general
medical principles. In the event of failure at relief, we have two other
strings to our bow--alcohol injections, and neurectomy of the nerve
involved. Alcohol injections are dealt with later. Neurectomy--after
Thiersch’s method of avulsion--is greatly preferable to all the older
methods of neurotomy, nerve-stretching, and nerve-division. These older
methods brought about in their train but transitory alleviation of pain.


=Neurectomy of the inferior dental nerve.= A transverse incision is made
through the skin and subcutaneous tissues at the level of junction
between horizontal and vertical rami of the jaw, extending from the
anterior border of the vertical ramus to the posterior border of the
same. The tissues are retracted and the masseter muscle exposed. The
muscle fibres are split in the vertical direction and the bone laid
bare. A ¹⁄₂ inch trephine is applied, and a disk of bone removed so as
to expose the inferior dental nerve at its entrance into the inferior
dental canal. The nerve is freed from the corresponding artery, divided
at the centre of exposure, and the two ends seized with forceps, twisted
and avulsed in such a manner as to destroy and remove the maximum number
of nerve-fibres. The disk of bone is replaced, the muscle fibres brought
together with a few catgut sutures, and the margins of the skin incision
approximated.


=Exposure of the infra-orbital nerve.= A curved incision is made through
the skin and subcutaneous tissues parallel to and below the
infra-orbital margin, the tissues retracted, and the small muscles
overlying the infra-orbital foramen divided or retracted so as to allow
exposure of the foramen. The nerve is isolated and divided. The
peripheral end is seized with forceps and avulsed. The central end may
be treated after similar fashion, or, preferably, again exposed in the
infra-orbital groove or canal, the tissues being peeled away from the
floor of the orbit and the nerve sought for as it traverses the
infra-orbital canal. With this object in view, it may be necessary to
gently break away the osseous roof of the canal before the nerve can be
exposed. It is then lifted up with a small hook, drawn through the
infra-orbital foramen, seized with forceps, and avulsed in such a manner
as to be torn away somewhere in the region of the spheno-maxillary
fossa. The wound is then sewn up.


=Exposure of the supra-orbital nerve.= The nerve is exposed through a
curved incision parallel to the supra-orbital margin, and so planned as
to be concealed by the eyebrow. The fibres of the orbicularis
palpebrarum are separated and the foramen identified. The nerve is
separated from its artery, divided, the peripheral portion avulsed, and
the central portion again exposed as it courses along the roof of the
orbit. For this purpose the tissues of the upper lid are detached from
the supra-orbital margin, the nerve delivered with the aid of a small
hook, brought out through the foramen, and avulsed in such a manner as
to be torn away somewhere in the region of the sphenoidal fissure. The
wound is then sewn up.


NEURALGIA MAJOR

Neuralgia major originates most commonly in the third division of the
nerve, less frequently in the second, and rarely in the first. Whichever
division be primarily affected, there is a very general tendency for
other branches to become involved, and this in a very definite way--the
pain spreading centrally from the nerve first involved, radiating to
other nerve-trunks so soon as they shall be reached. Thus, pain
originating in the inferior dental branch of the third division spreads
to the lingual and other branches of that division and then involves the
second division. Fortunately, whether the trouble originates in the
third or second divisions, the ophthalmic tends to escape or to become
less seriously involved--a fortunate circumstance considering the
terrible conditions associated with neuritis of that nerve, the
disastrous results on cornea, conjunctiva, &c.

The disease is undoubtedly of a progressive nature, originating without
rhyme or reason. It seldom becomes evident before the ages of 45 to 55,
affecting both rich and poor alike.

Wilfred Harris[69] collected 265 cases, and showed that the disease was
slightly more common in men than in women--144 to 131. There appeared to
be some predilection for the disease to involve the right side in
preference to the left--179 to 80. In 6 cases the affection was
bilateral.

Trigeminal neuralgia does not in itself lead to fatal results, but the
continuous pain, the want of sleep, and the difficulty experienced in
taking sufficient nourishment soon reduce the patient to such a
miserable condition that, unless relieved by the surgeon, amelioration
is sought in morphia or release in death.

Before proceeding further it will be convenient to enumerate certain
points aiding in the differential diagnosis between the true and
hysterical forms of trigeminal neuralgia.

       _True Neuralgia._                   _Hysterical Neuralgia._

  Patient old, probably over 50,     Patient young, more commonly of the
  and more commonly of the male      female sex.
  sex.

  Pain paroxysmal.                   Pain severe for long periods
                                     together.

  Vaso-motor, trophic and sensory    All these changes very rare.
  changes common.

  Pain strictly unilateral and       Pain variable in distribution,
  constant in site.                  radiating irregularly to the
                                     opposite side of the face.

The =pathology= of tic doloreux is most obscure. The parts requiring
examination are the peripheral nerve-trunks, the ganglion, the sensory
root, and the central nervous system. The last two regions may be
excluded, not only on the ground that research has failed to show any
constant structural changes, but also because the removal of the
ganglion may be regarded as curative of the disease. The ganglion itself
and the peripheral nerve-trunks remain for investigation.

In the peripheral nerve-fibres no constant material changes have been
observed. The epineurium, on the other hand, is almost invariably
shrunken and sclerosed. Considerable stress might be laid on this fact
unless it were also taken into consideration that the nerves were
examined in patients who had suffered from major neuralgia for prolonged
periods of time. Similar changes have also been observed in patients who
have never exhibited neuralgic symptoms.

In the ganglion itself the following changes have been observed:--(1)
arterio-sclerosis; (2) alteration in the character of the nerve-fibres
traversing the ganglion; and (3) adhesions between the ganglion and the
surrounding parts. All these changes, however, are so inconstant that
but little importance can be attached to them.

At the present time there is a disposition to regard trigeminal
neuralgia in the light of an ascending neuritis, originating
peripherally and ascending towards the Gasserian ganglion. Sir Victor
Horsley first pointed out that the ganglion acts as a barrier to the
further upward spread of the affection. This is proved by the success
obtained in the removal of the ganglion.


Symptomatology.


_Pain._ The onset of pain may be preceded by premonitory symptoms such
as tinglings, throbbings, and burning sensations in the parts
subsequently involved, whilst, in the earlier stages of the disease, the
pain may be more or less localized to the site of emergence of the nerve
from an osseous foramen.

In the earlier stages also the attacks, though severe, are paroxysmal,
of short duration, perhaps not lasting more than half a minute, and
definitely localized to some special nerve-trunk. During the periods of
remission the patient feels quite well. Gradually the pain increases in
severity, the periods of remission shorten, and the pain in its
distribution becomes more widespread, the neuritis--or whatever the
process may be--spreading centrally and radiating along the course and
distribution of such branches of the nerve as shall be encountered.

Paroxysms are a marked feature, occasionally of so severe a nature that
the patient falls to the ground as if struck by lightning, recovering
after a variable period of time.

In the later stages of the disease the pain may be almost continuous,
and the condition of the patient is truly miserable.

The attacks are often ushered in by the slightest stimulus--talking,
mastication of food, draughts, emotion, &c.--and, in order to avoid the
occurrence as far as possible, the patient abstains from talking, dreads
eating, &c. Dribbling from the mouth may be observed in those cases in
which the patient finds some relief in keeping the mouth open. It is
also frequently seen during the height of the paroxysm. At such stages
the patient is collapsed, with feeble pulse, shallow respiration, the
temperature subnormal, and the skin clammy. The attacks occur both
during the day and the night, sleep fails, and the body nutrition
suffers.

The site at which the pain originates can often be fixed by the patient
himself. Occasionally relief may be attained by pressure applied over
some particular part, by heat or by cold, or by some other method
discovered by the patient himself.

The attacks are often accompanied by twitchings of the muscles supplied
by the facial nerve, and, according to some investigators, by fibrillary
twitchings of the muscles of the region affected.

In the later stages, wasting of the muscles may be observed.


_Vaso-motor and trophic changes._ The skin and mucous membrane supplied
by the nerve involved become hyperæmic and hyperæsthetic, and, in the
more chronic cases, these changes may be associated with œdema of the
subcutaneous tissues--the clinical picture now closely resembling that
observed in some cases of angio-neurotic œdema.

Other symptoms of similar nature are herpes, increased salivation,
furred tongue (on the side of the lesion), sweating of the skin,
lacrimation, conjunctivitis, and keratitis.


_General decline in health._ This depends, not only on the difficulty
experienced in taking sufficient nourishment, but also on the moral
effect produced by the more or less continuous pain. In the more severe
cases emaciation is rapid.


Treatment.


1. _Therapeutic remedies._ The following drugs have been recommended.

Quinine, in large and increasing doses.

Arsenic, given in a similar fashion.

Gelsemium, in toxic doses, every few hours until tinglings in the
fingers and nausea show that the drug has been pushed far enough (Sir
Victor Horsley).

Methylene blue, in three-grain doses (Sir Watson Cheyne).

Iron, antipyrin, strychnine, cannabis indica, &c.

Morphia. This drug is undoubtedly beneficial in its results, but the
habitual use thereof is strongly contra-indicated, not only because of
the temporary benefit received, but also because of the necessary
increase in the quantity required to alleviate the pain. If persistently
used the patient gradually develops the morphia habit.

Some of these remedies suffice for the neuralgias minor, but with regard
to their action in cases of neuralgia major, their effect may be summed
up as follows: ‘True tic doloreux has been the therapeutic despair of
most physicians and surgeons,’[70] and ‘too often the operation is put
off till the patient is addicted to the morphia habit, depleted in
strength and vitality by drugs, sleepless nights, and years of intense
suffering’.[71]

Until quite recently, with the exception of these medicinal remedies,
the only other methods at our disposal in the treatment of trigeminal
neuralgia were Gasserian ganglion removal and other intracranial
operations on the three divisions of the fifth nerve. In 1906, however,
Schlösser[72] of Munich advocated the injection of alcohol into the
region of those foramina at the base of the skull through which the
nerve trunks emerged. As the result of these injections it was stated
that, although some slight degree of cutaneous anæsthesia frequently
resulted, yet that it was usually of an unimportant and transient
character, and that the pain subsided and finally ceased, remaining
absent for a variable period of time, usually about ten months. In the
event of recurrence the injection was repeated, each period of recurrent
pain being less intense and less prolonged, whilst the periods of
remission increased proportionately.

Whilst it is clear from the results obtained by those who have followed
in Schlösser’s footsteps, that alcohol injections are, as a rule,
reasonably satisfactory, yet it must be clearly understood that
beneficial results are not always observed, and that in the event of
failure the more radical intracranial operations must be carried out.


The technique of alcohol injections.

_Question of anæsthetic._ Freezing of the skin or other method of local
anæsthesia suffices to allow of the painless introduction of the needle.
A general anæsthetic should be avoided wherever possible, as the burning
sensation experienced by the patient when the nerve-trunk is encountered
greatly assists the accuracy of introduction.

_The needle._ The needle should be stout--10 cm. long, 1·5 cm. in
diameter, and graduated in centimetres up to 5 cm., and provided with a
blunt stilette.

_Introduction._ The skin is cleansed, the stilette slightly withdrawn,
and the needle introduced. After puncture of the skin the stilette is
pushed home, all further introduction being carried out with the blunt
advancing point. When in position, the stilette is withdrawn, and a
glass syringe, ready filled with alcohol, fitted to the needle and the
injection made.

_The solution._ Purves Stewart recommends the injection of 1-1·5 c.cm.
of the following solution:--

  Beta eucaine, 2 grains
  Absolute alcohol, 6 drs.
  Distilled water to the ounce.

Wilfred Harris advises 90 per cent. alcohol, preceded by a 2 per cent.
solution eucaine. He urges that two or three drops should be injected
slowly, and if the needle be correctly placed a sharp burning pain will
instantly be felt over the area of the distribution of the nerve,
lasting fifteen seconds or so and then dying away. Two or three more
drops are then injected, and thus ‘a few drops at a time, from 1 to 1·5
c.cm. are injected, the pain produced with each succeeding push of the
syringe being less and less’.

To reach the _foramen ovale_ (third division), the needle is introduced
through the cheek behind the last molar tooth, at the lower border of
the zygoma, at a point 2¹⁄₂ cm. in front of the descending root of the
zygoma. The blunt needle penetrates the masseter muscle and the
posterior part of the temporal muscle. It is then directed backwards and
slightly upwards till it impinges on the skull at the external pterygoid
plate. It is then pushed on, upwards and backwards, till it enters the
foramen ovale at a depth usually of about 4 cm. from the zygoma. In case
of difficulty in passing the needle through the sigmoid notch of the jaw
the mouth should be widely opened.

If the needle be directed too low it may penetrate the pharyngeal wall
or the Eustachian tube; if too far back, the middle meningeal artery.

To reach the _foramen rotundum_ (second division)--a rather more
difficult procedure--it is necessary to find the posterior border of the
orbital process of the malar bone, prolonging this line downwards to the
lower border of the zygoma and inserting the needle ¹⁄₂ cm. posterior to
this point. The needle is pushed horizontally inwards and the point
directed slightly upwards, the foramen being reached in the
pterygo-maxillary fossa at a depth of about 3 cm. from the zygoma. The
needle, for an average-sized skull, should never penetrate deeper than 5
cm. The structures pierced are the anterior fibres of the masseter and
the buccinator muscles. If directed too horizontally, the needle will
pass below the nerve and reach the spheno-palatine region; if too high,
the sphenoidal fissure may be reached and the branches of the third
nerve damaged, causing diplopia and dilatation of the pupil.

To reach the _sphenoidal fissure_ (first division), the needle is
introduced at the outer margin of the orbit, close within the
fronto-malar articulation, and passed along the outer wall of the orbit
to a depth of 3¹⁄₂ to 4 cm.

Needless to say, it is essential that these injections to the basal
foramina should only be carried out in the first instance after
experimentation on the cadaver.

In each case a single injection may suffice, but as a general rule it is
advisable to repeat the process after two or three days, and again at
longer intervals. It is not necessary that the nerve-trunks should be
pierced, but better results are obtained by so doing. The surface area
to which the particular nerve-trunk is distributed immediately becomes
anæsthetic, remaining in that state till the effect of the injection
shall have passed off. The masticatory muscles are paralysed. The
injection may be followed by paresis of the facial muscles, by œdema of
the lower lid, and by hæmatomata. These last-named results are, however,
transitory.


=Results.= Schlösser, who injects 15 to 20 minims of an 80 per cent.
solution of alcohol, reported in 1907 that he had treated 123 cases, the
average period of relief from pain being ten and a half months.

Wilfred Harris[73] reported on 38 cases, 31 of which were completely
relieved for periods varying from two to eleven months. In a more recent
communication he reports on 86 cases, in only 3 of which was no relief
obtained. In 7 cases the injection was made into the ganglion itself, in
anticipation of more permanent results.


=Operative procedures.= Intracranial procedures for trigeminal neuralgia
were formerly associated with so high a rate of mortality that they were
not regarded with favour. Of recent years, however, as the result of the
general improvement in technique, it has been clearly demonstrated that,
in experienced hands, ‘the ganglion can be readily exposed, hæmorrhage
and shock need no longer be considered elements of danger: the risks of
the operation are only those associated with every major operation.
Recovery from the effects of the operation is rapid; the patients are
frequently up and about on the third or fourth day, and the ultimate
results are, to say the least, most gratifying to the patient and to the
operator.’[74]

The following operations require consideration:--

1. Intracranial resection of the second and third divisions of the fifth
nerve (Abbé’s operation).

2. Operations for the removal of the whole or part of the Gasserian
ganglion (Hartley-Krause operation and its modifications).

3. Operations on the sensory root of the ganglion (Frazier’s operation).

_Intracranial resection of the second and third divisions of the fifth
nerve and operations on the ganglion itself_ resemble one another so
closely in their preliminary operative stages that they may be
considered together. After the usual preparatory treatment--in which
the shaving process may be confined to the temporal region--the
incision, commencing well above and behind the external angular frontal
process, passes backwards below the level of the temporal crest and
terminates immediately in front of the tragus of the ear. The front part
of the incision, as depicted in Fig. 91, is prolonged too far downwards.
It should not be carried further forward than the anterior margin of the
hairy scalp, any further downward prolongation tending to involve that
branch of the facial nerve which is distributed to the anterior belly of
the occipito-frontalis muscle.

The incision, carried out methodically, first involves the skin only,
pressure being applied by the surgeon on the one side and his assistant
on the other, so as to control bleeding. All divided vessels are at once
clamped. The operation may be a prolonged one, and in its later stages
bleeding from meningeal vessels and emissary veins may not be so readily
controlled. It is essential, therefore, that the earlier stages should
be as bloodless as possible.

[Illustration: FIG. 90. TO ILLUSTRATE THE OPERATIONS ON THE GASSERIAN
GANGLION. s.f., sphenoidal fissure; f.r., foramen rotundum; f.ov.,
foramen ovale; s.s., Frazier’s operation on the sensory root. The dotted
line = the line of section in removal of the lower two-thirds of the
ganglion (_Jonathan Hutchinson’s operation_). The shaded portions =
parts removed in intracranial resection of the second and third
divisions of the nerve (_Abbé’s operation_).]

The temporal fascia is next incised--slightly below the line of the skin
incision. Finally, the temporal muscle is divided--again at a lower
level than the fascial incision. Skin, fascia, and muscle are then
turned down to a zygomatic base. Some surgeons split the temporal muscle
in the direction of its fibres, a course, however, that tends somewhat
to cramp the operative field.

The trephine is applied to the bone, the surgeon aiming at striking the
angle between the anterior and posterior branches of the middle
meningeal artery. The bone-disk is removed. With the aid of craniectomy
forceps the bone is nibbled away, more especially in the downward
direction towards the base of the skull. It is essential that the
operator should get down as low as possible, for the lower the line of
attack the easier the approach to the ganglion and the less the damage
incurred by the brain (from retraction).

The opening in the bone, oval in shape, should present a diameter in the
vertical direction of about 1 to 1¹⁄₄ inches, and an antero-posterior
diameter of about 1¹⁄₂ inches.

The dura is stripped away from the base of the skull, partly with the
fingers and partly with the blunt dissector, and a flat, slightly
malleable retractor introduced along the floor of the middle fossa, the
dura and overlying temporo-sphenoidal lobe being gently lifted upwards.
The surgeon should take upon himself the responsibility of retracting
the brain, holding that instrument with the one hand and working inwards
with the other, directing his course towards the foramen spinosum
(middle meningeal) and foramen ovale (third division of the fifth
nerve).

During this stage hæmorrhage, derived mainly from the branches of the
middle meningeal, is often troublesome. It may be controlled by the
insertion of dry or wet gauze--in the latter case the gauze is soaked in
saline solution or sterilized water (at a temperature of about 110°
Fahrenheit)--or by the introduction of cotton-wool plugs to each of
which a silk thread is attached, for the purpose of facilitating their
final removal.

The middle meningeal artery acts as a guide to the foramen spinosum, a
foramen that lies immediately posterior and external to the foramen
ovale. In many cases the position of this artery so hampers the operator
in his manipulation that ligature is demanded. For this purpose
Cushing’s silver ‘clips’ will be found most serviceable. One clip is
applied to the artery immediately after its entry into the skull, the
other a short distance above, the vessel being divided between the two
(see Fig. 6).

The foramen ovale is then identified, the dura being stripped away from
the nerve trunk by blunt dissection. The surgeon then works inwards and
forwards to the second division of the nerve and its foramen, the
foramen rotundum. Hæmorrhage, in this case derived from emissary veins,
may again be troublesome. Considerable perseverance is required, and,
although each attempt at further separation of the dura from the bone
entails more oozing, the difficulties--except in the most exceptional
cases--may be overcome.

The _second and third divisions may now be resected_. For this purpose
it is essential that the two nerves should be exposed from the point of
their exit from the skull right up to the margin of the ganglion. Their
dural coat seldom requires to be incised with the knife, the membrane
being readily stripped away with the blunt dissector. When fully
exposed, the nerve trunks are picked up with a blunt aneurysm needle and
divided in two places, flush with the basal foramina and close up
against the ganglion. The intermediate parts are removed.

To prevent regeneration of nerve fibres--with consequent return of
symptoms--the basal foramina are blocked up with small ivory pegs--well
driven home--or with amalgam.

All gauze plugs are removed, the field of operation well dried, and dura
and brain allowed to fall back into position. The wound is closed, if
possible without drainage. In the event of considerable oozing a
cigarette drain should be inserted for twenty-four hours. The scalp-flap
is sewn up, skin, muscle, and fascia being united separately.

_Removal of the Gasserian ganglion._ There is some divergence of opinion
as to whether it is necessary to remove the ganglion entire or whether
it suffices to resect the lower two-thirds--that part through which the
fibres of the second and third divisions course--the upper third being
left intact. This latter course is advocated by Jonathan Hutchinson on
the grounds that (1) the first division is but rarely involved in the
neuralgic process, (2) its inclusion in the process of removal entails
some risk to the eye--conjunctivitis, keratitis, and sloughing of the
cornea, and (3) resection of the lower two-thirds of the ganglion, when
carried out in suitable cases, is but rarely followed by the development
of neuralgia in the first or ophthalmic trunk. Added to these facts, it
must be admitted that the complete removal of the ganglion is associated
with added operative risk--wounding of the cavernous sinus and injury to
the third, fourth, and sixth nerves.

The Gasserian ganglion lies in the cavum Meckelii, a depression on the
anterior aspect of the petrous portion of the temporal bone, and is
situated between the two layers of dura mater, the stronger on the upper
or cerebral side, the weaker between it and the bone. Under the
pathological conditions often existent in cases of trigeminal neuralgia,
considerable adhesion may be present between the ganglion and its
enveloping coats. Consequently, its complete exposure is often a matter
of considerable difficulty. The dura must be stripped away from the
outer aspect of the ganglion, firstly by dividing the membrane along the
border of the ganglion between the site of emergence of the second and
third divisions, and then by blunt dissection.

The ganglion and its efferent branches being exposed, _resection of the
lower two-thirds_ may be carried out. The second and third nerve trunks
are severed flush with the basal foramina, traction applied, and the
lower portion of the ganglion resected.

During the final stages, the manipulations of the operator are again
likely to be obscured by venous oozing and by the discharge of some
cerebro-spinal fluid. Patience, careful application of gauze plugs, and
good illumination of the field of operation are required to overcome
these difficulties. In some few cases the bleeding has been so profuse
that the operation has had to be abandoned for the time being, a fresh
attempt being made some days later. This course should, however, rarely
be necessary.

Similarly, if the operator should deem it necessary to remove the whole
ganglion, this procedure may now be carried out. The posterior part of
the ganglion is exposed, together with its sensory root. This root is
hooked forward with a small blunt-pointed hook and then divided.
Traction is applied to the ganglion and it is turned forwards, the three
terminal divisions being divided one after the other with the minimum
risk of injuring the cavernous sinus.


=Modifications of the Hartley-Krause operation.= With the object of
obtaining further manipulative room, some surgeons recommend the
formation of an osteoplastic flap. This method should never be adopted.
It is quite unnecessary, it prolongs the operation, and entails more
deformity. Others advise division of the zygoma, both in front and
behind, with downward displacement of the intermediate portion.
Burghard[75] recommends division and downward displacement of the zygoma
together with section of the coronoid process, this process being
turned upwards together with its attached temporal muscle.

From my own experience, I should regard all these modifications as quite
unnecessary, the Hartley-Krause operation permitting an adequate
operative field. The deformity resulting from all these more extensive
procedures must also be taken into consideration. The lines of incision
in the Hartley-Krause operation are more or less concealed by the hairy
scalp.

[Illustration: FIG. 91. TO ILLUSTRATE THE OPERATIONS FOR EXPOSURE OF THE
GASSERIAN GANGLION. _e_, The incision for Frazier’s operation; _f_, The
incision for the Hartley-Krause operation (in its most recent
modification, the front part of this incision is not carried so far
downwards, thus avoiding _b_², that branch of the facial nerve which is
distributed to the anterior belly of the occipito-frontalis muscle);
_c_, The intra-osseous portion of the anterior division of the middle
meningeal artery; _b_¹, The branches of the facial nerve to the
orbicularis palpebrarum, &c.]


=Operations on the sensory root (Frazier’s operation).= Charles Frazier
advocates the ‘physiologic extirpation’ of the sensory root of the
ganglion. The advantages claimed over other methods are as follows:--

1. _Control of hæmorrhage and avoidance of risk of injury to the
cavernous sinus_. The ganglion receives its main blood-supply from
below. Division of the sensory root leaves the base of the ganglion
undisturbed, and this cause of free bleeding is removed. With respect to
the cavernous sinus, the operation is confined to the root of the
ganglion and consequently the sinus is in no wise concerned.

2. _Simple technique._ The operation of division of the sensory root is
complete before the difficulties common to extraction of the ganglion
have commenced.

3. _Avoidance of injury to adjacent structures._ The cavernous sinus is
not touched; the sixth nerve, which is intimately related to the
ophthalmic branch, is not exposed; and the motor-fibres which, passing
beneath the ganglion, join the third division outside the skull, and
which are almost necessarily injured in the ganglionic operation, may,
in division of the sensory root, escape implication.

4. _Reduction in the rate of mortality._ The operation is said to be
more economical of time, to entail less hæmorrhage, and therefore to be
less dangerous.

5. _Absence of ocular changes._ After division of the sensory root
ocular changes are absent, due in part to the fact that the ocular
nerves are left intact, and also to the probability that ‘sympathetic
fibres pass to the eye after entering the trigeminal nerve through the
Gasserian ganglion’ (Spiller).

In the consideration of these advantages it should be noted that they
are mainly directed against procedures in which complete extirpation of
the ganglion is attempted, and are of less weight when contrasted with
the partial excision advocated by Hutchinson.


=Frazier’s operation[76] on the sensory root.= ‘A horse-shoe shaped
incision is made, beginning at the middle of the zygoma and terminating
a little below the apex of the lobe of the ear (see Fig. 91). The
musculo-cutaneous flap is made purposely a little larger than the
opening in the skull. An opening is made in the skull with a diameter
not exceeding 3 cm. and extending down as far as the infra-temporal
crest. The dura is separated from the base of the skull with a blunt
retractor as far as the foramen spinosum. The middle meningeal artery is
ligatured and the dura mater incised directly over the third division at
the margin of the foramen ovale and separated from the upper surface of
the ganglion as far back as the sensory root. The latter is picked up
with a blunt hook, grasped with forceps and divided or avulsed. It is
necessary only to expose the posterior portion of the ganglion; the
second and third divisions of the fifth, the structures on the inner
side of the ganglion, and the cavernous sinus, are left undisturbed.’


=Choice of operation.= There are both advantages and disadvantages to
each of the various operations enumerated. There are also other
operations. From my own experience I have come to the conclusion that
the two operations of choice are resection of the second and third
divisions of the fifth nerve and division of the sensory root. The
former of these two operations is carried out when the general condition
of the patient is not altogether satisfactory, presuming, of course,
that the neuralgia is limited to those divisions of the nerve. Under
more favourable circumstances excellent results are obtained by exposure
and division or resection of the sensory root, with, I think, the
minimum risk.


=The results obtained by operation.= The prevailing impression that
these operations are associated with a high mortality is totally
incorrect. From my own experience and from numerous recorded cases, the
mortality may be estimated at not more than 5 per cent.

The extent of anæsthesia resulting varies according to the nature of the
operation. Thus, if the upper part of the ganglion be spared or the
operation confined to the second and third divisions, the upper lid,
conjunctiva, cornea, and forehead escape. In any case, taste is but
little impaired, the posterior part of the tongue being supplied by the
glossopharyngeal and the tip and sides by the chorda tympani. In all
cases, except perhaps in Frazier’s operation, the motor fibres which
accompany the third division are almost always divided, with consequent
paralysis of the corresponding masseter, temporal, and pterygoid
muscles. The degree of discomfort and deformity resulting from such
anæsthesia and paralysis is, however, not very considerable, and in
contrast with the relief from the terrible pain, of very little import.
It is, as Jonathan Hutchinson says, the price which the patient has to
pay for the cure of the neuralgia.

With respect to recurrence of pain, there is every reason to believe
that the resection of the sensory root and the complete removal of the
ganglion are never followed by recurrence of pain. With respect to
Jonathan Hutchinson’s and Abbé’s operations, there is some divergence of
opinion. There would appear to be some cases recorded in which the
symptoms have recurred--often many years later. With regard to
Hutchinson’s operation I have no personal experience, but it is stated
that in some few cases the pain has recurred in the first division. I
believe, however, that I am correct in stating that this is denied by
Hutchinson from the experience based on his own cases. As regards Abbé’s
operation, recurrence may take place if the basal foramina are not
completely occluded, some few nerve fibres growing through the foramina
on either side of the occluding medium. Such complications have not
taken place in the cases in which I have carried out this operation.

Besides experiencing immediate and complete relief from pain, the
patients sleep well, eat well, and rapidly convalesce. For some two or
three days they may suffer from some headache, presumably due to the
necessary manipulations of the brain, but this, besides being relieved
by drugs, soon passes off. Frequently, the patients are up and about
within a few days.

Whatever the nature of the operation, the greatest care must be taken to
protect the eye on the affected side--the conjunctival sac is washed out
daily with a mild boracic solution and the cornea guarded from exposure
to air and dust by means of a glass covering fastened round the
forehead. This appliance should be worn for two or three weeks.

The =main difficulties and dangers of operation= are as follows:--

1. Hæmorrhage (from middle meningeal artery and cavernous sinus).

2. Infection.

3. Shock.

4. Ocular complications.

5. Later after-results--insomnia, restlessness, impairment of memory,
aphasia, and hemiplegia--all of which are dependent either on rough
handling of the brain or lighter handling of an already diseased brain.

[69] _Lancet_, November 27, 1909.

[70] Purves Stewart, _Brit. Med. Journ._, June 11, 1910, p. 848.

[71] Frazier, _Univ. of Philadelphia Bulletin_, April 1909.

[72] _Berlin. Klin. Wochenschrift_, No. 3, 1908.

[73] _Brit. Med. Journ._, June 11, 1910.

[74] Frazier, _Univ. of Philadelphia Bulletin_, April 1909.

[75] _A System of Operative Surgery_, vol. i, p. 437.

[76] _Univ. of Pennsylvania Medical Bulletin_, April 1909.




CHAPTER XI

TUMOURS OF THE SKULL-BONES


In this the last chapter of this work, I originally intended to deal
with tumours of the scalp and skull-bones. With respect to tumours of
the scalp there is, however, but little to say. The various conditions
are well recognized, their pathology is known, and there is in general
but little to relate. Tumours of the skull-bones come under a different
category and require some consideration.


=Tumours of the skull-bones.= The more important of these tumours are as
follows:--

  Osteomata.
  Sarcomata, primary and traumatic.
  Secondary sarcomata and carcinomata.


OSTEOMATA

Exostoses of the skull, though by no means of frequent occurrence,
occupy such definite positions that it would appear as if they were
dependent on some local governing cause. They develop most frequently in
the following positions:--

At the external angular frontal process.

At the frontal and parietal eminences.

In the region of the frontal sinus.

In the region of the external auditory meatus and mastoid process.

All pathological museums possess specimens illustrating the formation of
such exostoses, tumours of a like nature in other parts of the skull
being excessively rare.

In endeavouring to arrive at an explanation it would appear necessary to
direct one’s attention to tumours of a similar nature occurring in other
parts of the body, more especially in the long bones. There, it is well
recognized that their development is dependent on irregularities of
growth in the region of the epiphyseal lines, regions where activity of
growth is long maintained.

On referring again to the skull, similar features appear. For instance,
the frontal bone, besides possessing one primary centre for the frontal
eminence, has secondary centres for the external angular frontal
process, for the trochlear fossa, and for the nasal spine, and it is
highly probable that those exostoses which develop in the region of the
frontal sinus in reality arise from one or other of the secondary
centres situated in that region.

[Illustration: FIG. 92. IVORY EXOSTOSES OF THE SKULL.]

Both frontal and parietal eminences are also sites of active and
prolonged ossification, and the tumours there arising are to be
explained on a like hypothesis.

Similar features are to be observed with respect to those bony tumours
which develop in the aural region, the numerous centres of ossification
for the periotic capsule accounting satisfactorily for their origin.

Whether originating in the region of the frontal sinus or in the aural
area, the tumour naturally develops along the line of least resistance,
filling up the frontal sinus and growing into the external auditory
meatus and mastoid antrum.

More rarely, small exostoses develop on the inner aspect of the skull,
chiefly from the frontal bone in the region of the crista galli. In some
cases the inner aspect of the skull is studded with small bony tumours,
more especially along the line of the superior longitudinal venous
sinus.

[Illustration: FIG. 93. THE DEVELOPMENT OF THE FRONTAL BONE. A, Metopic
suture; B, Primary centre for frontal eminence; C, Secondary centre for
external angular frontal process; D, Secondary centre for trochlear
fossa; E, Secondary centre for nasal spine.]

These internal exostoses seldom give rise to pressure symptoms,
although, according to Wilks and Moxon,[77] they may push inwards the
dura mater and even lead to idiocy and epilepsy. I have seen several
cases of internal exostosis development, but in all cases their
discovery was accidental.


=Clinical characteristics.= Exostoses vary greatly both in size and
consistency. Some are densely hard--ivory exostoses--others possess a
covering of compact bone, whilst their interior is made up of cancellous
tissue continuous with that of the bone from which they arise. The
denser variety seldom attain any considerable size, but the less
compact, growing in the direction of least resistance, often attain such
dimensions as to be both unsightly and dangerous. Thus, a frontal
exostosis may invade the frontal air sinus and grow into the orbital
cavity, obliterating the sinus, interfering greatly with ocular
movements, causing protrusion of the globe and even destruction of the
eye.

An aural exostosis may block up the external auditory meatus, compress
the facial nerve, and lead to the development of a mastoid empyema.

It might also be added that there are a few cases on record in which a
frontal exostosis, by reason of extensive inward growth, has produced
cerebral symptoms--general compression and intellectual deterioration.


=Treatment.= In considering the question of treatment, it must be
accepted that, although of slow growth, some of these exostoses are
definitely progressive, tending to interfere with the character and
functions of the region with which they are anatomically situated. There
is also reason to believe that those secondary changes--sarcomatous,
myxomatous, &c.--which are occasionally observed in the exostoses of
long bones are also liable to develop in those cranially situated. The
question of treatment hinges, therefore, to a large extent on the nature
and position of the tumour.

When of the ivory type and growing from the flat bones of the skull, but
so situated that no marked deformity or pressure symptoms are likely to
ensue, they may be left alone, but when definitely progressive and
situated in accessible regions, they should be removed. Their exposure
is carried out by the formation of a suitable scalp-flap--designed as
far as possible so as to be subsequently hidden by the hairy scalp--and
the exostosis removed by the application to its base of a Gigli saw.
This method is greatly superior to the older procedures whereby the
tumour was chiselled away with hammer and gouge.

Occasionally the tumour is so dense and presents so wide a basal
attachment that it becomes necessary to attack from a more distant line,
cutting out a trench, deepened to the diploic tissue, circumferentially
around the tumour and levering away the central mass. When the tumour
extends more deeply, involving nearly the whole thickness of the skull,
it may be removed by the application of a small trephine immediately to
one side of the tumour, followed by the use of de Vilbiss forceps
circumferentially around the main mass, thus freeing it from its
surroundings. The resultant gap in the skull may be protected by one or
other of those measures enumerated in Chapter VI.

=Frontal and mastoid= exostoses often necessitate formidable operations
insomuch as their size and anatomical relations present considerable
difficulties (see Fig. 94).

The =indications for operation in the case of aural exostoses= are as
follows[78]:--

1. If there is middle-ear suppuration and signs of retention of pus.

2. When the pressure of the exostosis produces pain which cannot
otherwise be relieved.

3. If the exostosis nearly blocks up the meatus of both ears, and there
is prospect of each side becoming completely blocked in the near future.
Here operation is carried out on the worst side.

4. If the meatus is nearly blocked by the exostosis and the patient
going to a country where he cannot be within easy reach of a competent
medical man.

The =indications for operation in the case of a frontal exostosis= are
as follows:--

1. When the exostosis interferes with the actions of the ocular muscles,
causes proptosis and threatens the integrity of the globe.

2. When associated with pain which cannot otherwise be relieved.

3. When the exostosis leads to blockage of the accessory sinuses of the
nose, more especially when such blockage is associated with pus pent up
within.

4. When very unsightly.

The accompanying figure illustrates the deformity and dangers associated
with large frontal exostoses. The tumour developed from the inner angle
of the orbital cavity, pushing the globe forwards and outwards, with
diplopia and severe neuralgia.

It is barely possible to enter into the =operative details= suited to
frontal and aural exostoses--the operations are so atypical. It is
sufficient to say that the operation may be a very formidable one, that
the details must be carefully thought out, and that every precaution
must be adopted to avoid injuring neighbouring structures.

[Illustration: FIG. 94. AN EXOSTOSIS OF THE ORBIT.]


SARCOMATA, PRIMARY AND TRAUMATIC

Primary sarcomata of the skull, when compared to sarcomata developing in
other situations, is undoubtedly a rare disease. Still, many cases have
been recorded, and four have come under my own personal care, one of
which is depicted in the figure.

The disease is equally prevalent in the two sexes, and, excluding
chloromata (see p. 334), usually develops at or after middle life. The
growth may originate in the diploic tissue (as a myelogenous tumour), or
may spring from the pericranium. The cellular structure varies
accordingly. More commonly the cells are of the large round or spindle
type, and are proportionately malignant.

As regards site of development, the temporal bone (squamous portion) is
most commonly involved, next to which comes the frontal bone.

In considering the ætiology of sarcoma in general, _trauma_ must always
be taken into account, for it is an undoubted fact that it plays an
important part in the development of this dire disease. With respect to
the skull similar factors come into play. For instance, Fröhlking,[79]
after collecting 48 cases of sarcoma of the skull, found a definite
history of trauma in 9-21 per cent.

[Illustration: FIG. 95. AN EXTRINSIC SARCOMA OF THE SKULL.]

Ziegler[80] lays down the following essentials in establishing the
traumatic origin of the tumour: It must develop directly after the
trauma on the basis of the swelling or directly in the scar of the
wound.

The tumour must be palpable immediately after the acute swelling has
diminished.

At the site of the trauma constant or intermittent pain must be
present.

A considerable number of cases of sarcoma of the skull will fulfil even
these arbitrary conditions. Such sarcomata may definitely be labelled
‘traumatic’ sarcomata.

Whether dependent on injury or not, the _symptoms_ associated with
sarcoma of the skull vary according to whether the tumour is extrinsic
or intrinsic--whether, for instance, the growth develops in the inward
direction and presses on the brain, or grows from the pericranium and is
directed externally. _Intrinsic_ tumours, with the exception of some
local pain, œdema of tissues, and dilatation of superficial veins, give
rise to symptoms closely resembling those observed in intracranial
tumour formation. When _extrinsic_, the tumour varies in size, but is
necessarily attached to the bone, the base being the widest part of the
tumour. In the earlier stages the overlying skin, with the exception of
a few dilated vessels, is more or less normal. Later on, the integument
becomes adherent to the tumour, then red and inflamed, and finally
ulcerated, the growth now fungating to the surface. The tumour itself is
of variable consistency, first hard, then softer, and lastly
semi-fluctuating.

Pain, though not very severe, is more or less constant--of a dull,
aching character. The extrinsic tumours may, however, give rise to acute
neuralgic pain in the event of implication of cutaneous nerves; whilst
the intrinsic, in the later stages of the disease, lead to the more
severe types of headache observed in intracranial tumour formation.

Secondary nodules appear in other parts of the scalp--all appertaining,
in their clinical characteristics, to the primary growth; the cervical
glands become infected, and death results from repeated hæmorrhages,
pulmonary complications, &c., usually within one to two years from the
date of primary development.


=Treatment.= The removal of an extrinsic tumour should only be carried
out when the tumour is small and non-adherent to the tissues of the
scalp. With respect to the intrinsic variety greater circumspection is
required. The presence of cerebral symptoms and the inward extension of
the growth--verified by symptoms and by X-ray investigation--may be
regarded as implying that the conditions are beyond the reach of
surgery. In both varieties of tumour, extensive glandular implication
acts as a contra-indication to operation.

Under the more favourable conditions an attempt may be made at the
extirpation of the growth. The operation should be rendered as bloodless
as possible, for which purpose it is essential that the scalp-tourniquet
should be applied as a preliminary measure. A scalp-flap is then framed,
suited to requirements, and allowing of free exposure of the tumour and
surrounding healthy tissues. The skull is then trephined to one side of
the growth, and the disk removed. The dura is separated from the
overlying bone, and by the circumferential application of de Vilbiss or
other craniectomy forceps the central mass is isolated and removed.
During these manipulations free hæmorrhage may be experienced from the
numerous dilated diploic veins. For the arrest of this the surgeon
should have ready to hand, ivory pegs, bone-wax, and other aids for the
control of hæmorrhage (see Chapter II). The scalp-flap is then replaced.

[Illustration: FIG. 96. AN INTRINSIC SARCOMA OF THE SKULL.]

The gap in the bone may be covered in, at a later date, if the patient’s
condition is favourable.

The operation may be a formidable one, but records are to hand of 35
cases in which radical measures were adopted. Ten cases died from the
operation, 13 were well for periods varying from six months to six
years; and recurrence took place soon after the operation in 21 cases.


=Chloromata.= Chloroma, a peculiar type of sarcoma characterized by the
pale green hue of the tissues, usually develops in the young. The cells
are small and round, the pigment distributed in and around the cell
elements. The colour, said to be dependent on the presence of a
pigmented fat, is most intense immediately after the removal of the
tumour, fading rapidly on exposure to light.

The tumour develops from the periosteum of bones, more especially from
those which enter into the formation of the orbit and base of skull. In
fact, nearly all the cases reported have originated from the temporal
and orbital regions. Great rapidity of growth and early dissemination
throughout the viscera are conspicuous features--no organ of the body
can be said to be exempt from metastatic deposits. The meninges and
brain are early involved by direct extension.

Proptosis, as the result of cavernous sinus thrombosis and orbital
invasion, is a prominent and early symptom. Death results within six
months. No treatment, surgical or otherwise, is of any avail.


=Carcinoma= can only involve the skull-bones as a metastatic
deposit--more commonly in association with mammary cancer--or by direct
invasion from an overlying epitheliomatous scalp ulcer. In the former
instance, any radical treatment would be contrary to all surgical
principles. In the latter case, presuming that the cervical glandular
region is unaffected or capable of removal, the scalp ulcer should be
freely excised together with the whole thickness of underlying bone. The
resultant osseous gap may be covered in by means of a plastic flap
derived from neighbouring healthy tissue.

[77] _Lectures in Pathological Anatomy._

[78] Hunter Tod, _Diseases of the Ear_, p. 37.

[79] _Sarkomen des knöchernen Schädelgewölbes_, 1895.

[80] _Über die Beziehung von Träumen zu den malignen Geschwülsten_,
1895.




INDEX


  Abbé’s operation for tic doloreux, 60
  Abscess
    of the brain, acute traumatic, 247
      chronic otitic, 249
      multiple, 247
    of cerebellum, 258
      frontal lobe, 267
      temporo-sphenoidal, 263
  Acoustic tumours, 213
  Adhesions, osseous and meningeal, 195
  Alcohol injections in tic doloreux, 313
  Anæsthesia in head operations, 12
  Anosmia, 162, 220, 263
  Aphasia, 142, 155, 221, 258
  Apraxia, 221
  Arachnoid cysts, 203
  Arachnoid hæmorrhages, 158
  Arachnoid œdema, 168, 186, 203
  Aran’s theory of irradiation, 73
  Archibald
    on birth-hæmorrhages, 53
      compression, 168, 178
  Ataxia, 164, 224, 259
  Attitude in cerebellar lesions, 224, 262
  Aural exostoses, 326, 329
  Author’s operation
    for defects in the skull, 199
      hydrocephalus, 64
      subdural hæmorrhages, 156

  Basal cephaloceles, 34
  Base of skull
    fractures of, 73
    symptoms observed in fractures of, 89
    treatment in fractures of, 116
    weakness of, 73
  Basic foramina, their influence on basic fractures, 81
  Basic fracture, the typical, 77
  Bergmann (von)
    on cephaloceles, 36
      laceration of the brain, 165
      middle meningeal hæmorrhage, 143, 148
  Bilateral cerebellar exposure, 240
  Birth-fractures, 44
  Birth-hæmorrhages, 50
  Bland Sutton on dermoids, 56
  Blood-pressure
    in compression, 174
      concussion, 167
    in middle meningeal hæmorrhage, 140
      operations on the skull and brain, 11, 12
      tumours, 219
  Blood-cysts (subdural), 203
  Bone-flaps
    in cephaloceles, &c. 39
    (König-Müller), 196
    (osteoplastic re-section), 25
  Boullet on fracture of the mastoid bone, 108
  Bowen on subdural hæmorrhage, 153, 158
  Bowlby (Sir Anthony) on bullet-wounds, 297, 299
  Brain
    abscess of, 247
    compression of, 172
    concussion of, 166
    injury to, 159
    irritation of, 171
    tumours of, 210
  Brain-matter, escape of in basal fractures, 93, 101
  Broca’s area, 8, 221
  Bullet-wounds of the skull and brain, 294
  Burghard on Gasserian ganglion removal, 320
  Bursting and compression theories, 74

  Callen on injuries to the optic nerve, 95
  Campbell on cortical motor and sensory areas, 7
  Carcinoma
    of brain, 215
      skull-bones, 334
  Carotid artery, injury to internal, 148
  Cavernous sinus
    injuries of, 150
    thrombosis of, 288
  Cephalalgia, traumatic, 187
  Cephalhæmatomata, 49, 51
  Cephaloceles
    congenital, 31
    traumatic, 40
  Cerebello-pontine tumours, 213, 238
  Cerebral
    abscess, 256
    compression, 172
    concussion, 166, 177
    decompression, 120, 129, 242
    irritation, 171
    laceration, 159
    œdema, 168, 186, 191, 201
    tumours, 223
  Cerebellum
    abscess of, 256
    decompression of, 120, 242
    lesions of, 164
    position of patient in operations on, 12
    surface-marking of, 6
    tumours of, 223
  Cerebro-spinal fluid
    escape of from mouth, nose and ears, 91, 100
    source of, 91
  Cerebrum
    acute anæmia of, 167
    surface marking of, 6
  Chloroform as an anæsthetic, 12
  Chloromata, 334
  Chronic abscess of the brain, 249
  Chronic encapsuled abscess of the brain, 268
  Closure
    of the dura mater, 16, 236
    gaps in the skull, 39, 196
  Coma, traumatic and other forms, 179
  Comminuted, complicated and depressed fractures of vault, 126
  Compression, 172
  Concussion, 166, 177
  Contre-coup theory
    in basic fractures, 75
    brain injury, 160
  Control of hæmorrhage during operations on the skull and brain, 13
  Cortical motor and sensory areas, 7
  Cortical scars, 195
  Cotterill on hydrocephalus, 67
  Crandon and Wilson on hæmorrhages in basic fractures, 91, 99
  Cranial defects, 196
  Craniectomy, 19
  Cranio-cerebral topography, 1
  Craniotomy, 25
  Crowe and Cushing on the use of Urotropin, 116
  Cushing (Harvey)
    on birth-hæmorrhages, 52, 55
    decompression of the brain, 121, 235, 242
    epilepsy, 191
    hydrocephalus, 66
    pituitary tumours, 244
    trigeminal neuralgia, 318
  Cushing’s clips, 18
    tourniquet, 13
  Cysts
    of the brain, 215
    the meninges, 203

  Dana’s syndrome, 209, 225, 259
  Decompression
    cerebellar, 120, 242
    cerebral, 121, 129, 242
  Defects of the skull, closure or protection of, 39
  Dental chair position in head-operations, 12
  Depressed birth-fractures, 44
  Depressed fractures of the vault, 126, 129
  Dermoids, 55
  Duchaine on middle meningeal hæmorrhage, 147
  Dura mater
    hæmorrhage, external to, 133
    hæmorrhage, internal to, 150
    opening of, 19, 29
    suture of, 16, 236
  Duret
    on traumatic epilepsy, 193
    tumours of the brain, 245
  Dwight on fractures of the skull, 98

  Eighth nerve, involvement of in basic fractures, 102, 106
  Electric stimulation of brain in tumour exploration, 233
  Elevation
    of depressed birth-fractures, 45
    fractures of vault, 129
  Endotheliomata of brain and dura, 213
  English
    on remote effects of brain injury, 182, 187
    adhesions between scalp and meninges, &c. 195
  Epilepsy
    idiopathic, 190
    Jacksonian, 189, 192
    traumatic, 189
  Escape
    of air from air-sinuses in basic fractures, 95
    blood in basic fractures, 91, 96, 99
    brain in basic fractures, 93, 101
    cerebro-spinal fluid in basic fractures, 91, 99
  Ether as an anæsthetic, 12
  Exostoses of the skull, 325
  Explosive fractures of the skull, 113
  External table of skull, fracture of, 110, 133, 297
  Extra-cerebellar tumours, 225
  Extra-dural
    hæmorrhage, 135
    suppuration, 284
  Extrinsic sarcomata of the skull-bones, 332

  Falx cerebelli, 4
    cerebri, 1
  Fibromata of dura and brain, 213
  Fifth nerve, involvement of in basic fractures, 95, 101
  Fifth nerve, neuralgia of, 306
  Fissure
    of Rolando, 6
    Sylvius, 6
  Fissured fractures
    adult, 129
    infant, 49
  Foraminal occlusion in skull operations, 17
  Fourth nerve, involvement of in basic fractures, 95
  Fractures
    of base of skull, 73
    external table, 110, 133, 296
    internal table, 110, 296
    mastoid process of temporal bone, 104, 108
    skull, Teevan on, 110, 112, 294
    vault (adult), 68, 109
    vault (birth), 44
  Frazier (Charles)
    on cerebellar tumours, 239
    trigeminal neuralgia, 313, 321
  Frontal exostoses, 329
  Frontal lobe
    abscess of, 262
    lacerations of, 162
    tumours of, 219

  Gaps in the skull, closure or protection of, 196
  Gasserian ganglion, 310, 319
  Gauze coverings in operations on skull and brain, 13, 16
  Gigli saw in operation on skull and brain, 25
  Gliomata of the brain, 211
  Gowers on optic neuritis, 217
  Grafts, muscle, 18
  Grünbaum (and Sherrington) on cortical motor and sensory areas, 7
  Gutter fractures, 296

  Hæmorrhage, control of
    from bone, 17
    brain, 19
    meninges, 17
    scalp, 13
  Hæmorrhage
    conjunctival, 89
    extra-dural, 135
    occipital, 90
    ocular, 90
    palpebral, 90
    pia-arachnoid, 159
    retinal, 90
    subdural, 150, 153
    temporal, 96
  Hæmorrhage
    from ear, 96, 108
    internal carotid, 148
    middle meningeal artery, 135
    mouth, 91, 99
    nose, 91, 99
    venous sinuses, 150
  Hæmorrhage into temporal region, 96
  Hæmorrhages at birth, 50
  Hand-trephine, 21
  Harris (Wilfred) on alcohol injections, 310, 314, 316
  Hartley-Krause operation for trigeminal neuralgia, 316
  Head-injuries, remote effects of, 182
  Hernia cerebri, 291
  Hernial protrusions, 291
  Hill (Leonard) on brain compression, 175
  Holder on injuries to the optic nerve, 93
  Homonymous hemianopia, 222, 227
  Horsley (Sir Victor)
    on the regional mortality of brain tumours, 246
    pituitary tumours, 242
    the ‘two-stage’ operation, 230
  Horsley’s
    disk elevator, 23
    dural separator, 24
    gouge, 25
  Hudson’s trephine, 21
  Hutchinson (Jonathan) on trigeminal neuralgia, 310, 319, 323
  Hutchinson pupil, 141
  Hydrocephalus, 58
  Hysterical neuralgia, 310

  Idiopathic epilepsy, 190
  Inco-ordination of movement
    in cerebellar abscess, 260
    tumours, 224
  Inferior dental nerve, neurectomy of, 308
  Influence
    of air-sinuses in basic fracture, 79
    basic foramina in basic fractures, 81
    sutures in basic fractures, 78
  Infra-orbital nerve, neurectomy of, 308
  Injuries
    to the brain, 159
    head, remote effects of, 182
    internal carotid, 148
    venous sinuses, 152
  Intermusculo-temporal cerebral decompression, 121, 236, 267
  Internal carotid artery, injury to, 148
  Internal table, fractures of, 110, 112, 296
  Intra-cerebellar tumours, 225
  Intra-cranial birth-hæmorrhages, 52
  Irritation of the brain, 171

  Jacksonian epilepsy, 189, 192, 221, 262
  Jacobson on middle meningeal hæmorrhage, 142

  Keen-Hoffmann forceps, 23
  Keith on pituitarism, 226
  Koch and Filehne on cerebral compression, 167
  Kocher
    on compression, 176
    concussion, 166
    epilepsy, 190
  König-Müller flaps, 197
  Krause on pituitary tumours, 243
  Kredel’s hæmostatic sutures, 16, 21
  Krönlein on middle meningeal hæmorrhage, 138

  Lane’s forceps, 25
  Latent period in subdural hæmatocele, 154
  Lateral displacement of cerebellum, 238
  Lateral sinus
    injuries of, 150
    surface-marking of, 1
    thrombosis of, 281
  Line of basic fracture, typical line of, 78
  Lines of basic fracture, 82
  Little’s disease, 52
  Luciani on cerebellar abscess, 260
  Lucid interval in middle meningeal hæmorrhage, 139, 151
  Lumbar puncture
    in hydrocephalus, 61
      meningitis, 281
      subdural hæmorrhage, 54, 120, 155
      tumours, 227, 236
  Lyssenkow on cephaloceles, 32, 39

  Macewen
    on brain abscess, 290
      pus evacuation, 266
  Macewen’s suprameatal triangle, 5
  Malar tubercle, 4
  Mania (acute) after brain injuries, 201
  Mastoid antrum
    operations on, 269
    surface-marking of, 5
  Mastoid process
    displacement of, 108
    exostoses of, 329
  Mechanism of basic fractures, 73
  Meningeal cysts, 203
  Meningitis, 273
  Mental condition
    in abscess of frontal lobe, 263
      compression, 176
      concussion, 170
      irritation of the brain, 171
      lateral sinus thrombosis, 283
      meningitis, 279
      tumours of the brain, 216
  Middle meningeal artery, surface-marking of, 5
  Middle meningeal hæmorrhage, 135
  Morphia
    before and after operation, 11, 30
    in cerebral concussion, 178
      cerebral irritation, 128
      trigeminal neuralgia, 313
  Motor areas of cortex, 7
  Motor speech area, 8
  Multiple abscess of the brain, 247
  Muscle grafts, 18, 234

  Neuralgia
    hysterical, 310
    major, 308
    minor, 306
    of inferior dental nerve, 308
      infra-orbital nerve, 308
      supra-orbital nerve, 309
  Neurasthenia after head-injuries, 185
  Neurectomy of the branches of the fifth nerve, 308
  Nicholl on birth-fractures, 46
  Ninth nerve, involvement of in basic fractures, 106
  Nystagmus, 224

  Occipital cephaloceles, 33
  Occipital lobe
    lesions of, 164
    tumours of, 222
  Occipital sinus, surface-marking of, 4
  Olfactory nerve, involvement of in basic fractures, 94
  Opening of dura mater, 29, 119
  Optic nerve, involvement of in basic fractures, 95
  Optic neuritis
    in abscess of the brain, 254
      lateral sinus thrombosis, 283
      meningitis, 279
      tumours of the brain, 216
  Orbital aneurysm, 204
  Orbital hæmorrhage, 90
  Osteomata of the skull-bones, 325
  Osteoplastic re-section of the skull, 25, 229
    with decompression, 235

  Pachymeningitis, 274
  Palliative treatment of cerebral and cerebellar tumours, 241
  Palpebral hæmorrhage, 90
  Parietal prominence, 4
  Parieto-occipital fissure, 7
  Parsons on the pupil in middle meningeal hæmorrhage, 143
  Pathology
    of brain abscess, 251
      tumours, 210
  Paton on optic neuritis, 217, 218
  Percussion of skull in fractures of vault, 112
  Phelps
    on brain laceration, 160, 162
      bullet-wounds, 304
      middle meningeal hæmorrhage, 142
  Pia-arachnoid hæmorrhage, 159
  Pituitary tumours, 225, 243
  Plating of skull in traumatic and other defects, 198
  Pneumatoceles, 93, 108
  Position of patient in head-operations, 12
  Powell on traumatic insanity, &c., 202
  Precautions against the development of shock, 11
  Preparation of operative field, 13
  Preparatory treatment, 10
  Pringle on percussion of the skull, 112
  Prognosis
    after decompression, 243
    in brain abscess, 290
      cavernous sinus thrombosis, 290
      lateral sinus thrombosis, 290
      meningitis, 290
  Proptosis
    in basic and brain lesions, 90
      cavernous sinus thrombosis, 289
      orbital aneurysm, 206
  Protection of gaps in the skull, 196
  Pulsating exophthalmos, 205
  Puncture of the ventricles, 61, 236
  Punctured fractures, 132
  Pupillary changes in middle meningeal hæmorrhage, 142

  Radical treatment of cerebral and cerebellar tumours, 229, 237
  Reading, cortical area concerned in, 9
  Regional mortality
    in basic fractures, 133
      brain tumours, 245
  Reid’s base-line, 6
  Remote effects of head-injury, 182
  Results after operation
    on abscess of the brain, 290
      alcohol injections for tic doloreux, 316
      basic fractures, 133
      brain tumours, 245
      bullet-wounds, 304
      Gasserian ganglion removal, 323
      middle meningeal hæmorrhage, 147
      subdural hæmorrhage, 158
      traumatic epilepsy, 200
        insanity, 201
  Retinal hæmorrhages (Fleming on), 90
  Retraction of the head and neck
    in cerebellar abscess, 260
      tumours, 224
    in meningitis, 280
  Rivington on pulsating exophthalmos, 204
  Rolando, fissure of, 6

  Safety-valves in middle meningeal hæmorrhage, 96, 139
  Sarcomata
    of bone, 330
      brain, 211
  Scalp-tourniquet
    author’s, 15
    Cushing’s, 13
  Schlösser on alcohol injections for tic doloreux, 313, 316
  Sensory cortical areas, 7, 8
  Serous meningitis, 273
  Seventh nerve, involvement of in basic fractures, 102, 106
  Shaving of scalp, 10
  Shaw (Claye) on general paralysis, 203
  Sheen’s bullet-forceps, &c., 301
  Sherrington and Grünbaum on cortical areas, 7
  Shock (cerebral), 166
  Shock, precautions against, 11
  Sincipital cephaloceles, 34
  Sinus pericranii, 150
  Sinuses (air), influence on in basic fractures, 79
  Sinuses, thrombosis of, 281, 288
  Sinuses (venous), injuries of, 150
  Slow cerebration, 140
  Smell, registration of, 9
  Speech areas, 8, 163
  Stage of depression in concussion, 168, 170
  Stage of reaction in concussion, 168, 170
  Stereognosis, 9
  Sterilization of skin, 11
  Stewart (Purves) on tic doloreux, 314
  Stromeyer on sinus pericranii, 150
  Subconjunctival hæmorrhage, 89
  Subdural hæmorrhage, 150
  Summary of theories _re_ basic fractures, 89
  Superior longitudinal sinus
    injuries of, 150
    surface-marking of, 1
  Supra-meatal triangle (Macewen), 5
  Surgical emphysema, 93, 108
  Sylvian point and fissure, 6
  Syphilomata of brain, 214

  Taste, registration of, 9
  Technique of operations on the skull and brain, 10
  Teevan on fractures of the internal table, 110
    bullet-wounds, 294
  Temperature in relation to head-injuries, 114
  Temporal crest, 4
  Temporal hæmatomata, 96
  Temporo-sphenoidal lobe
    abscess of, 256
    injuries of, 164
    tumours of, 222
  Tenth nerve, involvement of in basic fractures, 106
  Thiersch’s method of neurectomy, 308
  Third nerve, involvement of in basic fractures, 95
  Thrombosis
    of cavernous sinus, 288
      lateral sinus, 281
  Tod (Hunter)
    on abscess of the brain, 249
      aural exostoses, 329
      lateral sinus thrombosis, 283
  Traumatic
    cephalalgia, 187
    defects in the skull, 196
    epilepsy, 189, 192
    insanity, 201
    mania, 201
    neurasthenia, 185
    orbital aneurysm, 205
  Tuberculomata of the brain, 214
  Tuberculous meningitis, 275
  Tumours
    of brain, 210
      skull-bones, 325
  Twelfth nerve, involvement of in basic fractures, 107

  Urotropin
    Crowe and Cushing on the use of, 116
    routine use of, 118

  Vault
    birth-fractures of, 44
    fractures of, 109
  Venesection in cerebral compression, 119
  Ventricular puncture, 62, 236
  Ventriculo-abdominal drainage, 66
    subdural drainage, 63
  Vertigo
    in cerebellar abscess, 259
      tumours, 224
  Vilbiss (de) forceps, 25
  Visual impressions, registration of, 9
  Vorschütz’s safety-pins, 16, 17, 21

  Wagner on osteoplastic re-section of the skull, 25
  Walton on middle meningeal hæmorrhage, 143
  Weber (Parkes) on hydrocephalus, 58
  Wiesman on middle meningeal hæmorrhage, 139, 141, 147
  Writing, cortical area concerned in, 9

  X-rays
    in bullet-wounds, 294
      fractures of the skull, 112
      tumours, 228

  Yawning
    in abscess of the cerebellum, 262
      lesions of the cerebellum, 165

  Ziegler on traumatic sarcomata, 331
  Zygoma, 4




  Transcriber’s Notes


  Depending on the hard- and software used and their settings, not all
  elements may display as intended.

  Inconsistent spelling, hyphenation, capitalisation, formatting and
  lay-out have been retained, except as mentioned below.

  The heading hierarchy has based on the contents and/or lay-out of the
  text due to the inconsistent formatting and lay-out in the source
  document. Consequently, this hierarchy (and any auto-generated tables
  of contents based thereon) do not necessarily reflect the author’s
  intent.

  Figs. 18 and 71, as well as Figs. 3, 58 and 68 and their respective
  captions and references in the List of Illustrations are identical in
  the source document.

  Page 39, Ssamoylenko: more commonly transcribed Samoylenko.

  Page 99, table, bottom row: the data do not add up to the total; the
  data and the total do not result in the percentage given.

  Page 115, van Benedin: possibly an error for van Beneden.

  Page 134, table: mortality with 59 survivors and 29 fatalities is 33%,
  not 37%. Some other calculated percentages elsewhere in the text are
  erroneous as well.

  Page 196: the Intersection symbol ⋂ is used to indicate the shape
  only, it is not used in its operator sense.

  Page 252, two-saced: as printed in the source document; possibly an
  error for two-faced.

  Page 312, 1. Therapeutic remedies: this is the only numbered
  sub-section in this section.


  Changes made

  Illustrations have been moved outside text paragraphs; footnotes have
  been moved to the end of the respective chapters.

  Some obvious minor typographical errors have been corrected silently.

  Page 68: “see Figs. 29 and 50” changed to “see Figs. 29 and 30”

  Page 146: “(see Fig. VI)” changed to “(see Fig. 6)”

  Page 174: “mesencaphalon” changed to “mesencephalon”

  Page 280: “tâche cérèbrale” changed to “tâche cérébrale”;
  “_Treatment._” changed to “=Treatment.=”

  Page 321, Fig. 21 (caption): closing bracket added after “the anterior
  belly of the occipito-frontalis muscle”