Endoscopic management of spontaneous meningoencephalocele of the lateral sphenoid sinus

Object. Spontaneous meningoencephaloceles of the lateral sphenoid sinus are rare lesions that are hypothesized to result from persistence of the lateral craniopharyngeal canal. Prior reports of the management of this lesion have been limited by its relative rarity. The objective of this paper is to report the theoretical etiology, surgical technique, and outcomes in patients undergoing endoscopic repair of spontaneous meningoencephalocele of the sphenoid sinus. Methods. The authors conducted a retrospective review of a multiinstitutional series of 13 cases involving patients who underwent endoscopic repair of spontaneous meningoencephalocele of the lateral sphenoid sinus. The surgical technique and pathophysiological considerations are discussed. Results. The clinical manifestations included CSF rhinorrhea (85%), chronic headache (77%), and a history of meningitis (15%). The endoscopic approaches to the lateral sphenoid sinus were transnasal (39%), transpterygoid (23%), and transethmoid (39%). Two patients (8%) had postoperative CSF leaks, one of which closed spontaneously and one of which required revision endoscopic closure. All patients were free of leak at most recent follow-up. One patient experienced postoperative meningitis in the early postoperative period. Conclusions. Endoscopic endonasal closure is an effective modality in the treatment of spontaneous meningoencephaloceles of the lateral sphenoid sinus. If the sphenoid sinus has extensive lateral pneumatization, adequate exposure may require a transpterygoid approach.