Destructive hydrocephalus: a proposed new category.

A case is reported with hydrocephalus subsequent to neonatal intraventricular and intracerebral hemorrhage. Hydrocephalus was diagnosed as obstructive, secondary to subarachnoid hemorrhage. However, the lateral ventricle in the hemisphere in which the intracerebral hemorrhage occurred dilated much more than that in the contralateral hemisphere. Hydrocephalus occurring in regions of the brain that have suffered destructive changes from a cause other than that of the hydrocephalus, as in this reported case, is proposed as a new category, ("destruction hydrocephalus"). It is to be distinguished from hydrocephalus with dilated ventricles due simply to increased intraventricular pressure. In "destructive hydrocephalus" dilatation of the ventricles occurs irregularly and rapidly, leading to secondary cerebral destruction. Therefore, treatment to prevent the progressive cerebral damage is required immediately.