bones are wanting altogether, and sometimes their place is supplied by the enlargement of those in the neighbourhood. An excess of development is observed in those cases when more or less of a second head is formed; and premature closure of the satures and fontanelles constitutes another, but a less, degree of the same general condition.-Rokitansky's Pathological Anatomy, vol. iii, p. 205.-P.H.B.]

CHAPTER III.

ENCEPHALOCELE OR HERNIA OF THE BRAIN.

Encephalocele or hernia of the brain, consists of a tumour formed by the passage of a portion of cerebrum or cerebellum through an aperture of the skull. It is a vice of conformation of the same kind as anencephalia, only it is less considerable.

We are ignorant of the causes of encephalocele. It is a disease characterized by a small, soft, transparent, rounded tumour, without any change of colour in the skin, narrow at the base and as if pedicellate. It is most commonly observed on the occiput, then at the forehead, the anterior fontanelle, the posterior fontanelle, the lamboidal suture, the internal angle of the eye and the temporal region. Pulsations synchronous with those of the pulse are observed, and an expansive movement simultaneous with that of the respiration. The child experiences no bad symptom if the tumour is not touched; when it is rather strongly compressed, it vomits, sleeps, or becomes convulsed. It continues stationary for a long time, but it ends by growing in a rapid manner, which interferes with the development of the intellectual faculties and predisposes to meningitis or to inflammation of the brain. This tumour has been observed to burst spontaneously in consequence of the gangrene of its walls, whence meningitis and death.

Most of the children labouring under encephalocele usually die in early infancy. Some subjects go beyond and live to twenty-five and thirty-three years, of which Lallemant and Guyenot have seen instances, but these are exceedingly rare exceptions.

Hernia of the brain, in a subject advanced in years, might be mistaken for a wen or a sebaceous cyst of the scalp, and in a child, for a cephalæmatoma or an erectile tumour, as has sometimes happened even to very distinguished surgeons. The diagnosis of encephalocele is, in fact, sometimes very difficult; however the softness, demitransparence, reducibleness, pulsations synchronous with the pulse, and the expansion which coincides with the respiratory movements, may serve to establish it.

The prognosis of encephalocele is exceedingly unfavourable and 'depends on the size of the tumour, and on its structure, according

Si me live

as it is more or less covered by the skin. Death is the most usual

termination of this disease.

In the patients who die, the following lesions are observed: a tumourlin Ginnes which is generally situated at the occiput either covered by the skin. or not; in the latter case it is by the dura-mater, but this is very rare. The skin is red, thin, furnished with hairs at its circumference but not at the summit; beneath the skin is the sub-cutaneous cellular tissue and the epicranial aponeurosis, then the pericranium, and lastly the dura mater lined by the arachnoid.

In this sac a portion of the cerebrum or cerebellum is enclosed, or ay Con even the entire cerebellum. The nervous substance is more or less changed and constricted at the situation of the opening of the cranium where it is slightly strangulated. It sometimes contains serum in its tumor interior if the hernial portion belongs to a lateral ventricle. In other cases it is covered by the serum, in variable proportions which may reach nearly seventeen ounces.

Lastly, a bony or fibrous opening, of greater or less size, establishes the communication between the sac of the encephalocele and the skull. It presents no peculiarity.

[Cotunnius was the first, we believe, to draw attention to the fact of their being, in the normal condition of the nervous centres, a fluid present in the cavities of the brain, and beneath the sub-arachnoid covering both of it and of the spinal cord. Magendie elaborated the subject, and termed the fluid cerebro-rachidian. Magendie considered two ounces to be its ordinary amount-Cotunnius four. According to the former, the fluid in the ventricles communicates with that in the cerebro spinalsub-arachnoid space, and accumulates in the greatest quantity when that space affords greatest capacity. A few years ago it was stated by Breschet, after his cli examination of very many bodies at the Hôpital des Enfants Malades, that in the fœtus, in infants of the full time, and in children of from six months to one year old, a certain though variable amount of fluid is to be found in the anterior or median ventricle, or in the cavity of the septum lucidum. This cavity, well described by the brothers Wenzel and Tiedemann, is found to be larger the younger the child. Morgagni gave the first hint that too great an effusion of the cerebroste rachidian fluid might produce an important disease; and Breschet particularly calls attention to the existence of this natural hydrocephalus (as he calls it), as not being directly a disease in itself, but as a circumstance disposing more or less to pathological phenomena, and, therefore, to be regarded as an important point in reasoning upon the cause of intra-cranial effusions in general, and especially upon congenital hydrocephalus.

Dr. Behrend, in an able paper (Journal für Kinderkrankheiten, 1849), the design of which-founded upon several cases-is to show that spina bifida, congenital hydrocephalus, and encephalocele arise from one and the same cause; and a highly interesting case that occurred to him, in which the two former affections were present with hyderencephalocele over the brow, seems to support in a satisfactory manner the point which is maintained in the paper in question.

This idea, hinted at by Morgagni, more prominently alluded to by Breschet, and further illustrated by Dr. Behrend himself, that there is a common cause at the base of these affections, or between the former and the latter, and that variety of encephalocele termed hyderencephalocele and congenital hydrocephalus.

A writer in the British and Foreign Medico Chirurgical Review, states that he is of opinion "that there is sufficient support for assuming that during intra-uterine life, in consequence of an abnormal activity of the vessels of the meninges, a superabundant quantity of the cerebo-rachidian fluid is effused, and that this fluid, normal when in proper quantity, presses unduly against the ossific walls, breaks through them when it finds least resistance, and pushes before it the membranes of the nervous centres, causing them, with the integuments, to protrude in the form of a tumour; the particular affection which is found being determined by the particular seat and extent of this fluid, and by the point at which it meets with least resistance. In Behrend's case, when the fluid was evacuated from the tumour over the spine, the tumour of the forehead gradually diminished, and the distended and protuberant fontanelle fell. It was clear to the observer that there was an intimate connection between the three phenomena. It might be replied, that in spina bifida and those cases of encephalocele in which solution of continuity, not sutural, or deficiency of bony walls, exists, such conditions of the latter, and the permission of protrusion through them, are dependent, primarily, upon an incompleteness or want of progressive perfect performance of the action of osteosis than on any local influence exerted upon the cranial of the vertebral walls, in perfect independence of whether the action formative of bone be normal or otherwise. But since, in Behrend's case, none of the bony tissues of the skeleton showed any signs of want of that amount of osteosis which should be expected to exist in relation to the age of the child, except in the particular spots of the cranium and spine where protrusion existed; and since in many other cases of various forms of encephalocele and congenital hydrocephalus, with deficiency of bony continuity, other than sutural, the like fact existed; and not only this but, as shown by Aurivill, Malacarne, Hartell, and others, that save in those localities immediately involved, the bones of the skull have been in many cases thicker than ordinary; we believe that we have sufficient reason for assuming that the protrusion of the external tumour does not primarily depend upon a low development of the power of ossification. On the contrary, we believe the power of forming bony matter to be quite in its normal intensity, and that, if it were even much stronger, the pressure of the fluid would interrupt its action locally, absorption of the earthy matter would ensue, and a retrograde metamorphosis take place in the cartilaginous and ossific formations. We may observe, too, that it has been stated by Behrend, that in cases of hirni and anen-cephalia, when originally intra-uterine hydrocephalus existed, and the calvarium became not only thinned, separated, or fissured, but quite disappeared, and the brain also, the rest of the skull was almost always unusually thick. Why in one case the pressure of the fluid should be mainly exerted at the top of the cranial vault, in another at the occiput, in a third at the brow, in a fourth at the temporal bones; or why the rachidian fluid should be more effused than the cerebral (or vice versâ), and press in one instance on the lumbar, or in another on the cervical spine (Ollivier's case), we do not pretend to say. Sometimes the distension of the parts which ensues in congenital hydrocephalus is equal; in some instances the direction of the pressure is much stronger towards one side. In many of these latter cases it is evident that such direction of pressure in a particular line is dependent upon the greater amount of effusion on the one side than on the other. Klein found the left side of the encephalon widely distended, presenting the appearance of a mere bladder, whilst the right side had not departed from its natural form. In another case, the left ventricle was so distended as to reach the bulb of the olfactory nerve.

We do not, however, mean to deny that there do occur cases of vices of comformation of the cranial bones, which are independent of a mere local pressure from fluid within, and which may even permit of the existence of some forms of encephalocele.

But we believe, that in the varieties of intra-uterine and congenital disorders we have Crain! more especially alluded to, their theory of formation is such as we have cursorily hinted at. Even in cases like the one mentioned by Billard, in which there was complete absence of the petrous portion of the left temporal bone, and, through the space thus formed, a considerable portion of the brain protruded, in a sac formed by the meninges and skin, but void of true scalp, it is probable, as the relater observes, that there existed in the uterus some kind of projection, as a polypoid growth, &c., which, coming into contact with the part of the cranium alluded to, had caused destruction of the scalp, &c. ; or else that there was some vice of conformation.

of the pelvis of the mother, which caused pressure to be exerted on a particular y 18!.6

portion of the uterus as it enlarged.”—P.H.B.]

TREATMENT.

It is impossible to reckon on the radical cure of encephalocele. However, we must try, in the limits of a wise prudence, the means which surgery places at the disposal of the practitioner.

If the tumour can be reduced without inconvenience to the child, it should be replaced in the skull and retained there by means of a leaden plate, or one of stiff leather, kept in place by a bandage. If the complete reduction is impossible, we should still try palliative com-pression, which arrests the increase of the tumour, keeps it of a diminished size, and yet permits the development and the use of the different functions. In this case the compression is practised by means of bandages and concave plates applied on the encephalocele.

Some practitioners have endeavoured to remove the tumour by alte in means of the ligature alone, or by ligature followed by excision.

All the children treated in this manner have died of meningitis, in

consequence of the operation.

Incision has been several times practised, either advisedly to empty the encephalocele of the liquid, or in consequence of an error in diagnosis. Some children have recovered: but why an incision, if it, duction is only attempted to evacuate the fluid? Would it not be better simply to have recourse to a fine puncturation, or to a subcutaneous puncture?

Several practitioners have done this, and Adams amongst others.

A puncture may be made in the coats of the tumour with a sewing matin needle, and this puncture is sufficient to allow the serum to escape. Adams has thus withdrawn half an ounce from one puncture of an Aud encephalocele. The liquid may be reproduced, but at the end of some days it is again let out by the same method, and the operation, is repeated seven or eight times if it appears necessary. By combining this method with methodical compression, the rupture of the sac is

prevented, and the increase of the cerebral hernia also; the skin

becomes stronger, and the children are placed in the most favourable circumstances for their recovery, or at least for the preservation of their existence.

[Several cases are recorded in English practice.

One of Mr. Lyon's cases proves the value of compression in relation to hyderencephalocele, and several facts are on record which illustrate the treatment by puncture in this disease. They are not very strong in its favour certainly, but they are are sufficient to show that when the contents of the tumour are entirely fluid, or much fluid and a small portion of brain, and compression alone is unavailing in reducing them, the idea of puncturation is not entirely to be set aside. Accounts of cases so treated by Lyon, Adams, Earle, and Dendy may be referred to; and to the deductions to be arrived at from reasoning by analogy on the case of spina bifida punctured by Abernethy, one so treated by Sir A. Cooper, and one more lately by Dr. Steevens, of New York, as also from some of the instances in which chronic hydrocephalus has been favourably subjected to a like procedure. In Mr. Lyon's case, when the dura mater and the pia mater lined the interior of the tumour, the latter was first punctured on the right side of the nose, five days after on the left; the third day after the child died. In Mr. Adams's example the tumour underwent puncturation seven times with success, allowing the escape of fluid each time, and finally leaving a solid tumour apparently formed by a protruded portion of the brain. Mr. Earle repeated the operation nine times, the child surviving nearly two months from the first puncturation. Mr. Dendy, during the space of about nine days, punctured thrice with a grooved needle, allowing the escape of about twelve ounces of fluid, the child dying on the tenth day.-P.H.B.]

CHAPTER IV.

ON CEPHALÆMATOMA.

The word cephalæmatoma should be exclusively applied to the effusion of blood formed between the pericranium and the bones of the skull. In consequence of an injudicious extension, it has been employed for certain collections of blood situated above the pericranium, or effused within the cavity of the skull but external to the dura mater.

There are then, 1st, the cephalæmatoma, properly so called, epicranial cephalaematoma; 2nd, pseudo-cephalæmatoma, supracranial; and, lastly, 3rd, intracranial cephalamatoma.

1ST. ON EPICRANIAL CEPHALÆMATOMA,

The true cephalæmatoma, termed epicranial, is a disease but little known-scarcely referred to by Mauriceau, Levret, Bandelocque, &c.; better described by Michaelis and Palletta; and more completely studied in Germany by Naegele, Hore, Zeller, and in France by MM. Valleix and Paul Dubois. These two last authors, especially, appear to me to have brought to bear on this question all the information necessary to its complete elucidation.

Epicranial cephalæmatoma is, probably, incorrectly regarded as the result of difficult labour, and on the pressure of the head of the fœtus