MENINGIOMA RESEMBLING AN EPIDERMOID TUMOR

A case of retro-orbital meningioma who presented to the Department of Surgery, Neuro-surgery Unit of Tikur Anbessa Hospital in June 1993 wit h a progressive right eye proptosis is described. Exploration through a right frontal craniotomy showed a well circumscribed and encapsulate d thickened bony tumor that had a cavity containing a cheesy-yellowish oily material. The lesion was successfully shelled-out. The preoperat ive diagnosis was meningioma. However, based on its intraoperative mac roscopic appearance, mode of presentation, and location of the lesion an impression of an epidermoid tumor (cholesteatoma) was made. The res ult of histologic examination turned out to be meningioma (psammomatou s type). Literature review on both conditions, the pathologic characte ristics and clinical features are discussed briefly.