Papers of the Week

Acquired (non traumatic) 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 MRI showed an intracranial tumor of the left frontal convexity associated with a herniation of the frontal brain (encephalocele) into the left nasal cavity. CT-scan confirmed the anterior skull base defect. The intracranial tumor was totally excised following a left frontal craniotomy with a good outcome. Pathological 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 non traumatic encephalocele) probably occurred due to long-term increase of the intracranial pressure generated by the meningioma.