[Ectopic meningioma of the ethmoid sinus: case report and a review of the literature].

A rare case of ectopic meningioma of the ethmoid sinus is reported. A 57 year-old male patient was admitted with complaints of anosmia and headache. Computed tomography revealed a relatively high-density mass in the bilateral ethmoid and sphenoid sinuses. The mass was markedly enhanced after intravenous administration of contrast medium. The cerebral angiography showed tumor stains fed by bilateral internal and external carotid arteries with right side dominance. The tumor in the ethmoidal sinus was removed by otolaryngologists at first and then the tumor in the sphenoid sinus was removed using sublabial transseptal sphenotomy. The histological examination resulted in a diagnosis of transitional meningioma with psammoma bodies. The tumor in this case is suspected to have originated from heterotopic meningocytes or meningocytes accompanying the perineural sheath of the olfactory nerve.