opinion that the organic malady had remained latent, until the occurrence of the fall. The same author gives an interesting table, showing the weights of the brains of fifty children aged fifty months and under, who died of various diseases; he concludes that all inflammatory affections have a tendency to increase its weight, and that this increase is mainly due to the greater amount of blood contained in the cerebral vessels.

ATROPHY.

The converse of hypertrophy is a condition which, as we have already had occasion to remark, is the result of a natural process in old age; but it is also the effect of disease; or of an arrest of development. In consequence of long-standing, exhausting illness in children, Dr. West informs us that the brain is found far from filling up the cavity of the skull, so that a knife may be passed, in many places, between it and the cranial walls. The same appearance is met with in the adult, and the consequence is that serum is effused between the brain and its envelops, in order to supply the defect; the convolutions become thinner, and they are separated by broader sulci. There is some discoloration of the tissue, and the veins of the pia mater are observed to present a varicose appearance, owing to the loss of the support which they experience. We also meet with partial atrophy; this is generally of a secondary character, owing to pressure exerted upon individual parts by tumors or other adventitious growths, apoplectic cysts in the arachnoid or peripheral lesions. The absorption induced by the effect of pressure is accompanied by induration of the adjoining layers of the cerebral tissue. The atrophy that is found as a result of arrest in the functions of a peripheral nerve, as in the case of the optic thalamus in amaurosis, is a marked instance of the influence of functional derangement upon nutrition, propagated to a distance.

In idiots, we have congenital atrophy of the entire, or of portions of the brain; in the brain of old insane persons it is common, according to Neumann's statement, who has examined fifty cases of the kind, to find the posterior lobes and their convolutions more atrophied than other parts; Sir Charles Bell, Cruveilhier, and Lallemand record cases of epilepsy and hemiplegia, accompanying congenital atrophy of one hemisphere, though not necessarily associated with a destruction of the intellectual powers.

CHAPTER X.

THE BRAIN-MORBID GROWTHS.

THE products of a perverted state of nutrition and of a cacoplastic condition of the blood, which are found in other tissues of the body, also occur in the brain, though for the most part in a secondary form; associated with or following upon their deposit elsewhere. They have certain features in common, owing to the anatomical relations of the brain; thus, they all generally assume a rounded shape, owing to the uniform pressure to which they are subjected on all sides; they are not, as for instance in the lungs, received into a mould by which their external configuration is in a measure determined; they do not proceed to a similar degree of development from the early danger to life which they induce; they are liable to produce softening of the tissues in the immediate vicinity, and, owing to the impairment of the circulation, are commonly accompanied by an effusion into the ventricles. The last two circumstances are those to which we may probably refer the symptoms observed during life; for the presence of tumors in the brain is often not discovered until the death of the patient from disease of some other organ, and where they had maintained this quiescent state, the cerebral tissue in the vicinity exhibits no traces of degeneration. Thus, Messrs. Tonnellé, Léveillé, and others, who have devoted especial attention to the occurrence of cerebral tubercle, conclude that the tubercles in themselves do not give rise to any symptoms, but that the cerebral symptoms accompanying them are exclusively due to the intercurrent inflammation. The difficulty of early diagnosis, and the fact of adventitious growths in the brain occurring almost exclusively in the secondary form, place them more especially in the range of the morbid anatomist; they are even less amenable to therapeutic treatment than when they have found a nidus in the abdominal or thoracic organs. The form in which we most frequently meet with them is tubercle and cancer.

TUBERCLE.

Tubercle, as we have already had occasion to see, is a frequent concomitant or source of meningeal inflammation. Tubercular deposit in the cerebral tissue, like the former, is equally a disease peculiar to childhood; but the two are not necessarily associated together. Tuber

See Rilliet and Barthez, Traité Clinique des Maladies des Enfants, tom. xiii. p. 552, seq.

cle in the brain may affect any part of the organ; it occurs in the shape of rounded nodes varying in size from a pin's head to a walnut or hen's egg; the deposits are not generally numerous, and their size bears an inverse ratio to their frequency. It is most common to find only one or two, and of an average size of a chestnut. Dr. Baly has recorded a case in the reports of the Pathological Society' of a young man who died in the Millbank prison, and in whose brain tubercles were found; only two were discovered in the left hemisphere, but the number in the right are estimated to have been as many as fifty, varying in size from a grain of pearl barley to that of a barley-corn; the same case is also instructive as showing the great rapidity with which the deposit may occasionally take place under circumstances favoring the disease; for the patient was admitted into the prison on the 30th December as a healthy subject; after a few days was attacked with headache, and on the 19th of January following, he died with all the symptoms of an acute cerebral affection. The case appears to disprove the dictum of Rokitansky, that cerebral tubercle never occurs in any but the chronic

form.

The tubercle presents the appearance and consistency of soft yellow cheese, and while miliary granulations are peculiar to the meningeal form, the yellow tubercle is the variety almost invariably met with in the brain. We are unable to determine whether the deposit takes place in this form; the more extended application of the microscope will best decide the question; since the microscopic characters of tubercle are sufficiently determined to give a positive answer. Rokitansky is of opinion that tubercle in the brain, does, in part at least, commence in the gray translucent form, for portions of a tubercular mass are sometimes found in that state. In any case, however, he adds, it may continue for a short period only in that form, and soon pass into the stage of the yellow cheesy tubercle. The microscopic elements are the same granulated nuclear corpuscles of an ovoid or somewhat irregular shape, interspersed with granular blastema and particles of oily matter found elsewhere; according to the amount of inflammatory action exerted in their vicinity we shall also find more or less glomeruli, with other traces of its effects. The tubercle is generally surrounded by a delicate cyst, and when, which occasionally happens, the tubercular matter proceeds to the stage of softening, the superficial observer may mistake the morbid appearances for those of a simple abscess of the brain. The concurrence of tubercle in other parts, together with the aid of the microscope, will assist in fixing the real character of the affection. The frequency of tubercle of the brain in children is a point not to be forgotten in the treatment of their diseases, and is one of the reasons why the overstraining of the mental faculties of a delicate child is so much to be reprobated. Physicians who have had the most extensive experience in these matters agree as to the rarity of its occurrence in the adult; thus, Cruveilhier never met with a single case, and Lugol, in the large hospital of St. Louis, has only seen eight instances, in none of which any symptoms of the disease were manifested during life.

Session 1850-51, p. 34.

It is a singular fact, which we gather from the statistics of MM. Rilliet and Barthez, that sex appears to exert a marked influence upon the occurrence of cerebral tubercle; in each variety, the males are considerably more liable to the affection than females; of forty-four cases, we find twenty-nine occurring in boys, and fifteen in girls. The fact is confirmed by the statistics of our own medical writers: an analysis of fifteen cases reported by Dr. Abercrombie and others, establishes a similar proportion; ten of these cases were males, and five females. It is, however, right to state that Dr. Hennis Green's' statistics contradict this fact; his observations were made at the same hospital as those of MM. Rilliet and Barthez, and, of the thirty cases which he has collected, fourteen occurred in boys and sixteen in girls.

The deposit of tubercular matter sometimes occurs in patches of irregular shape and size, on the surface of the brain, beneath the pia mater,1 but commonly, as we have already seen, it forms nodules within the cerebral tissue. It is often met with both in cerebrum and cerebellum at the same time; the number of cases in which it occurs in one or the other alone is about equal; the pons varolii is, in rare cases, the only seat of the deposit.

In the lungs, we frequently meet with satisfactory evidence of the power of the system to reject and cure tubercle; we are not possessed of similar proof with regard to the brain; the only analogous process is that in which the vitality of the deposit seems utterly destroyed, and cretification results; this is a metamorphosis which sometimes, though rarely, takes place in cerebral tubercle. We must not confound with cretification of tubercle, certain gritty or sabulous masses found in the brain; thus, our notes contain the history of a case, in which, on a vertical section of the cerebellum, the knife grated upon some calculous formations, imbedded in the tissue, and intimately adherent to it; there proved to be, on each side, three or four irregularly crystallized masses, which broke up easily on pressure, and were not affected by either liquor potassæ or acetic acid. There was no other perceptible disease of the cerebral tissue, but the choroid plexuses were covered with concentric corpuscles. Andral' gives, as a great curiosity, an analogous case, in which, however, the "ossifications" were inclosed in a cyst.

CANCER

Next in frequency to tubercular deposit we find the various forms of cancer, all of which, excepting the epithelial variety, are met with in the brain. There are no symptoms peculiar to the disease, beyond the effects resulting from pressure; and even they do not appear to be in any way commensurate with the size of the deposit. The form which it assumes is that of infiltration, without any definite limits, or of a tumor surrounded by a cyst; in the former case, there seems a continuity of tissue between the cancerous mass and the nerve-tissue. The

Medico-Chir. Trans. vol. xxv. p. 192.
p. 209.

2 See Mr. Dunn's case, ibid.

3 Clinique Médicale, t. v. 719.

same law, with regard to the predominant liability of the cerebrum compared with the cerebellum, applies in the present instance; thus, in forty-three cases of cancer of the nervous centres alluded to by An

Cancerous tumor, occupying the upper portion of the posterior cerebral lobe of a man aged 54, brought into St. Mary's Hospital comatose and hemiplegic, in which state he remained until death. The central portion was dense and fibrous, of a yellow color, and consisting of fusiform fibre-cells: the external portion soft, cream-colored, or pink, composed of a variety of compound cancer-corpuscles. The whole was surrounded by a red vascular margin.

dral,' we find thirty-one occurring in the cerebral hemispheres, and five in the cerebellum; the remainder were thus distributed: three were found in the pituitary gland, one in the corpus callosum, and three in the spinal cord. The same author, by an analysis of the cases collected by him, establishes, numerically, the relation commonly found to prevail with regard to the frequency of primary cancer in the nervous centres; in ten of the forty-three cases only, or less than one-fourth, was there any carcinoma in other organs. As a result of local injury, we meet with a species of fungoid growth of the brain, which has been termed hernia cerebri, but which is very different from the hernia cerebri to which allusion has been made, in the section treating of congenital hydrocephalus. In consequence of a fracture of the skull, the brain appears to sprout forth in the shape of a vascular, medullary growth. It appears as if the brain, released from its confinement, luxuriated in its newly-acquired liberty. Extensive suppuration is generally found accompanying this form of hernia, within the brain. We are not in possession of any microscopic examination showing the exact nature of the growth.

In addition to tubercular and cancerous deposits we also meet with melanotic, fatty, and fibrous growths, and cysts in the encephalon.

It was long doubted whether melanosis ever occurred in the brain, and it certainly is rarely found in this locality. Sir Robert Carswell, however, gives a specimen of two tumors of this description, which

Clinique Méd. t. v. p. 633.

2 Pathological Anatomy, 1888, Art. Melanoma, pl. ii.