Ependymal Cyst of the Sylvian Fissure

ABSTRACT

Cerebral ependymal cysts are very rare. About 30 cases have been reported in the literature. They mimic arachnoid cysts clinically and on imaging studies but are different from arachnoid cysts in pathological findings. They are believed to arise by the sequestration of a small segment of the primitive ependymal lining into either the cortical mantle or the perimedullary mesh. They occupy the central white matter of the frontal or temporoparietal lobes. The authors describe a case of septate ependymal cyst involving left sylvian fissure. The clinicopathological features, treatment, and results of previously reported cases are reviewed, and the etiology and pathogenesis of these cysts are discussed.