ABSTRACT
Cerebral Arteriovenous malformations (AVMs) are presumed congenital anomalies of the blood vessels, which can increase intracranial pressure by uncertain mechanisms. We report the rare case of a 55-year-old male patient who complained about CSF rhinorrhea. Persisting CSF leakage prompted CT, which evidenced a bone defect in the right middle cranial fossa with protruding brain tissue. The diagnosis of a sphenoidal meningoencephalocele was made. Neuroimaging evidenced an AVM Spetzler Martin V. The lesion was targeted via an endonasal approach with resection of the herniated brain tissue and closure of the bony and dural defects. The postoperative course was uneventful without recurrence of the CSF fistula. Documentation of these cases is essential to come up with standardized therapeutical protocols and follow-up. Nevertheless, conservative management of the AVM and surgical repair of the bone defects is an appropriate approach in the first instance, depending on the morphology and characterization of the AVM.