Endoscopic Endonasal Approaches

Pathologies of the anterior skull base, including the cribriform plate, planum sphenoidale, and tuberculum sellae, have traditionally been approached through several transcranial and transfacial approaches. More recently, keyhole approaches have been utilized with success even for large tumors, avoiding the morbidity of larger exposures and minimizing brain exposure and retraction. Endoscopic endonasal approaches are an extension of this philosophy and, in carefully selected patients, may be an excellent alternative, offering a direct line of site from an endonasal trajectory. Furthermore, bilateral optic canal decompression can be safely and effectively accomplished via the endonasal route. Here, we describe the endoscopic endonasal transtuberculum/transplanum and transcribriform approaches, focusing on indications, limitations, functional preservation techniques, and complication avoidance. In the theme of functional preservation, we also propose that the supraorbital keyhole craniotomy be considered as an alternative to the transcribriform approach to preserve olfaction.