Benign intracerebral cysts treated with internal shunts: review and report of two patients.

Two elderly women with symptomatic benign intracerebral cysts are reported. Before treatment, they both had developed moderate, but slowly increasing, symptoms from a cyst in the left hemisphere, which included epileptic seizures and right hemiparesis. During local anesthesia, an internal cystosubarachnoid shunt was inserted. After the operation, the cyst size was reduced markedly, with a corresponding improvement in the symptoms. A review of reported cases of benign intracerebral cysts is given. The average age of these patients is surprisingly high for a presumed congenital condition. There is a female preponderance, but the previously reported overrepresentation of left-sided lesions is not found in cases described after the introduction of computerized tomographic imaging.