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.
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.
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.
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.
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.
A
B
Fig. 24. A Case of Depressed Birth-fracture. A, Before operation; B, After operation. (For further description, see text.)
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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, 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]
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 (congenital). | Dermoids. | Cephalhæmatomata. |
|---|---|---|
| Present at birth. | Present at birth. | Usually appears after birth. |
| In middle line, especially over occiput and base of nose. | In middle line, especially over anterior fontanelle. | Always to one side of the middle line, and usually over the 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 whole or in part. | Irreducible. | Very slightly, if at all. |
| Perhaps swells up on straining. | No alteration. | Very slightly, if at all. |
| Perhaps associated with cerebral symptoms. | No cerebral symptoms. | No cerebral symptoms. |
| Gap in skull felt. | Depression in bone common, actual gap comparatively rare. | Deceptive raised margin, no actual central depression. |
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.
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, 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.
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.
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.
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.
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).
This operation may be carried out through the anterior fontanelle, through the frontal bone, or over the descending cornu of the lateral ventricle.
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.
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.
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 1⁄4-1⁄2 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.
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.