A certain amount of fluid, more or less coloured, bathes the surface of the clot ; and if the child live long enough the liquid may become enclosed in a species of cyst formed by more or less complete adhesion of the edges of the false membrane to the surface of the arachnoid covering. Some times the cyst is loculated, and the contents may increase in quantity by subsequent secretion. In a case reported by 1NIM. Rilliet and Barthez a double cyst was found, each chamber containing more than half a litre of fluid. When the collection of fluid is thus considerable, it presses out wards the fontanelle and the bones of the skull so as to form a real hydro cephalus.
It is rare to find hemorrhage in the ventricles ; but it may occur either in the walls of the lateral ventricles or into their cavities. Haemorrhage into the substance of the brain is also an uncommon lesion, although it may occur in infants and children of any age. It is seldom copious. Usu ally when it takes place it is in the course of some other form of illness, and perhaps on this account often escapes recognition during life. The blood is seen in minute points scattered about the cerebral tissue, or may be found collected in little cavities in the brain-substance. These two forms are about equally common. The larger collections of blood vary in size from a pea to a walnut. Around them the brain-tissue is normal, or tinted with rose colour, or slightly softened. The haemorrhages may be found at any part of the brain-substance, but are much less common in the cerebellum than in the cerebrum. Besides haemorrhages we often find in these cases much congestion of the brain ; and there may be also other lesions, such as meningitis and even tubercles of the brain, as in a case to be afterwards referred to.
Cases of aneurism of a cerebral artery in young subjects are almost in variably associated with endocarditis, and it is generally held that the ar terial dilatation is the consequence of embolism. It is probable, also, that cerebral hemorrhage in the child is more often the result of aneurism than is commonly supposed, for this may be easily overlooked. As Sir William Gull has observed, "when death takes place from changes around the aneurism, as by pressure or softening, the sac itself may present such ap pearances that unless a minute dissection be made of it, its true nature may not be discovered." The mechanism by which the aneurismal dilata tion is produced is doubtful. Dr. Ogle attributed it to the impaction of the fibrinous clot, and supposed that this afterwards softened and involved the coat of the vessel in the process. Dr. Goodhart has suggested that in many cases the clot is given off from a valve the seat of ulcerative endo carditis, that this poisons the part where it lodges and "leads to acute softening of the arterial wall by inoculating it with its own inflammatory action.'l This explanation is not, however, of universal applicability.
symptoms of meningeal haemorrhage are unfortunately far from being characteristic of the lesion to which they are owing. This form of intracranial haemorrhage; indeed, may give rise to no symptoms at all. According to M. Parrot, in infants' reduced by long-continued bad feeding to a cachectic state meningeal haemorrhage is not unfrequently found, although during life nothing unusual in the condition of the child had been noticed to excite a suspicion of this serious complication. On the other hand, in new-born babies extravasation of blood into the arach noid sac may be accompanied by violent convulsions and end in death within a few hours. Such a case is recorded by Valleix. A well-developed, healthy-looking male infant received a violent bruise on the shoulder two days after birth. He seemed to be going on favourably when, on the sixth day, he was seized with strong convulsions, which were repeated with violence, and in three hours the child was dead. On examination of the body a large clot was found in the arachnoid sac ; the veins of the pia ma ter were swollen with blood ; the substance of the brain was injected ; and the superior longitudinal sinus was filled with a whitish, semi-transparent, gelatinous thrombus. In this case the convulsions must not be attributed entirely to the No doubt the thrombosis had a great share in the production of the symptoms, and it was apparently the cause of the extravasation. Convulsions are, however, a common consequence of arachnoid hinmorrhage and repeatedly recur.
Legendre has described a febrile form of meningeal haemorrhage in which the disease begins with vomiting and pyrexia. Convulsive seizures soon come on, limited at first to the ocular muscles and giving rise to a. slight squint. The child sucks well, probably from thirst, and his bowels are in a normal state. Soon contractions are noticed of the fingers and toes, and general convulsions follow, both tonic and clonic, during which consciousness is lost and the face becomes of a dusky red tint. For a time the convulsions are comparatively infrequent, and in the intervals the child is heavy and drowsy. After a few days the heaviness deepens into stupor, the intervals between the fits become shorter and shorter, and towards the end of the illness the infant is almost constantly convulsed. The fever persists throughout, and death is often hastened by an intercurrent in flammatory complication of the lungs.