Choroid plexus cyst in the lateral ventricle causing obstructive symptoms in an adult.

This case of a rare symptomatic choroid plexus cyst in the lateral ventricle, which presented with papilledema and decreased vision, is the first such lesion found in an adult. Five earlier reported cases, all in children, are discussed, as are the limitations of computerized tomographic (CT) scanning and the need for further radiological studies to establish the diagnosis preoperatively. Metrizamide ventriculography with CT scanning is used to define the lesion and plan an operative approach.