The Surgery of the Skull and Brain

by Louis Bathe Rawling

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.