Hydrocephalus caused by increased intracranial venous pressure: a clinicopathological study.

A child developed progressive communicating nonobstructive hydrocephalus as a result of increased intracranial venous pressure. The child had been treated for congenital heart disease at age 3 weeks by surgical creation of an anastomosis between his superior vena cava and right pulmonary artery. Although his cardiac symptoms were alleviated, intracranial venous hypertension resulted, giving rise to progressive head enlargement and other signs of hydrocephalus. Postmortem examination at age 3 years disclosed no other lesions that could have caused the hydrocephalus. Increased intracranial venous pressure can lead to either pseudotumor cerebri or hydrocephalus, the former in children 3 years or older, the latter in infants 18 months or less. Possible mechanisms accounting for these differences are discussed.