hydrocephalus

hydrocephalus, accumulation of cerebrospinal fluid (CSF) in the ventricles, or cavities, of the brain, causing progressive enlargement of the head. Normally, CSF continuously circulates through the brain and the spinal cord and is continuously drained into the circulatory system. In hydrocephalus the fluid accumulates in the two large lateral ventricles, and the brain and skull become enlarged because of the accumulation of fluid. Hydrocephalus may be described as either communicating, in which the obstruction to...