Abstract
A 62-year-old-man was admitted to the hospital with complaints of headache, nausea and gait disturbance. Neurological examinations disclosed truncal ataxia and broad based gait. Magnetic resonance images demonstrated a cystic tumor, 4cm in diameter, in the cerebellar vermis, the margin of which was enhanced by Gadolinium-DTPA. At operation, the tumor was reddish, highly vascular, and had no continuity with the fourth ventricle, and it seemed to be a hemangioblastoma. It consisted of clear cells, showing perivascular pseudorosettes on light microscopy and the tumor cells were immunoreactive for glial fibrillary acidic protein(GFAP). Therefore, we diagnosed this case as a clear cell ependymoma in the vermis. Clear cell ependymoma is a rare variant of ependymoma and that in the posterior fossa is reviewed and discussed.
