Interhemispheric glioependymal cyst associated with agenesis of the corpus callosum--case report.

A male neonate was admitted because prenatal ultrasonography indicated central nervous system abnormalities. Neurological examination showed no abnormality except for electroencephalographic spike activities. Magnetic resonance imaging revealed a cystic lesion in the left interhemispheric fissure, agenesis of the corpus callosum, and microgyria in the left frontotemporal lobes. Cerebral blood flow (CBF) was diffusely reduced. The cyst wall was partially removed and a cyst-peritoneal shunt procedure was performed. The histological diagnosis was glioependymal cyst. The spike activity disappeared and CBF dramatically improved after the operation.