Intracerebral polyposis. Case report.

A 25-year-old man presented with nontraumatic cerebrospinal fluid rhinorrhea and meningitis. On investigation, he was found to have a multiloculated intracerebral cystic lesion of the right frontal lobe with a bony lesion inside the cyst, just above the right cribriform plate. Surgery revealed multiple grape-like cystic pedunculated lesions with narrow stalks attached to a bony outgrowth which was adherent to the right cribriform plate. Macroscopically and microscopically, the excised lesions were similar to nasal polyps.