A case of sphenoid sinus meningoencephalocele repaired by an image-guided endoscopic endonasal approach.

We report a Japanese patient with a complaint of unilateral watery nasal discharge. Analysis of the nasal discharge showed it to contain high levels of sugar and transferrin, which indicated cerebrospinal fluid (CSF) rhinorrhea. A diagnosis of sphenoid sinus meningoencephalocele was easily made on the basis of the CT, MRI and nasal discharge findings. We performed surgery by an image-guided endoscopic endonasal approach (IGEEA). An image guidance system (IGS) was used to confirm the position of the bone defect and the prolapsed brain lobe. We resected the brain lobe, and used fat tissue and fascia to create an extracranial-intracranial blockade. As of 18 months after the operation, there is no evidence of infection or CSF leakage. The IGEEA enabled us to successfully repair the middle skull base using a multi-layer sealing technique, while the IGS allowed us to confirm the anatomical structures and successfully avoid causing collateral damage to the surrounding tissues. This case exemplifies the beneficial effect that of the development of surgical support equipment on the operative approach that is now indicated for sphenoid sinus meningoencephaloceles: the endonasal approach has largely replaced other approaches, such as lateral rhinotomy.