Brain Herniation into Nasal Cavity Secondary to Large Convexity Meningioma.

Abstract

Acquired (nontraumatic) brain herniation through the ethmoid is rarely associated with an intracranial mass away from the anterior skull base. A 55-year-old diabetic woman presented with progressive frontal headache, anosmia, and blurred vision without rhinorrhea. Brain magnetic resonance imaging showed an intracranial tumor of the left frontal convexity associated with a herniation of the frontal brain (encephalocele) into the left nasal cavity. A computed tomography scan confirmed the anterior skull base defect. The intracranial tumor was totally excised after a left frontal craniotomy with a good outcome. Pathologic examination revealed a meningothelial meningioma. However, the patient and her family refused any surgery for the ethmoidal encephalocele. In our case report, this rare phenomenon (secondary nontraumatic encephalocele) probably occurred due to long-term increase of the intracranial pressure generated by the meningioma.