Cerebral white-matter hypoplasia.

Twelve patients, including three sisters, with lifelong severe intellectual impairment and neurologic defects were found to have generalized hypoplasia of the cerebral white matter, with corresponding enlargement of the ventricular system. Gray-matter structures were remarkably intact. Reactive cellular changes (gliosis, phagocytosis, inflammation) were absent. To our knowledge, this particular syndrome has not previously been delineated in the extensive literature on cerebral palsy. The abnormalities in these cases could result from the effects of a selectively acting tissue-damaging factor, such as has been postulated in perinatal telencephalic leukoencephalopathy, but the factors underlying the disorder are still unknown.