Epidermoid cyst of the third ventricle. A case report

We report a case of epidermal (or epidermoid) cyst, in a 36-year-old man wh ich developed in the third ventricle. Clinical manifestations were headache s and memory disturbances. On CT scan the tumor occupied the entire third v entricle but was mainly developed on the left side. On CT reconstructed ima ges, the floor of the third ventricle was clearly visible. Using a trans-ve ntricular approach, the tumor, closely related to the left part of hypothal amus, was totally removed. Later on, because of persistent hydrocephalus, a ventricular shunt was inserted. An aseptic meningitis occurred and resolve d spontaneously. The patient exhibited a postoperative transitory Korsakoff 's syndrome. postoperative endocrine investigations showed hypopituitarism. Some intra-ventricular epidermal cysts have been reported, especially invo lving the fourth ventricle. Their development into the third ventricle is u nusual, and in early reports their precise origin appears doubtful. Althoug h they have no characteristic radiological features, the location of epider mal cysts is clearly defined by the CT scan and especially MRI. It would be possible to totally remove epidermal cysts of the third ventricle, avoidin g the risk of recurrence.