A rapid and safe middle fossa approach to the geniculate ganglion and labyrinthine segment of the facial nerve

Abstract

The middle fossa approach provides neurotologic surgical access to lesions of the geniculate ganglion and the labyrinthine portion of the facial nerve as well as to the internal acoustic canal, and therefore helps preserve cochlear function. Although this approach is widely used, surgeons are still not certain which anatomic landmarks are best to locate the facial nerve and internal acoustic canal without causing labyrinthine damage. The purpose of this article is to describe a fast and safe technique to expose the geniculate ganglion and the labyrinthine portion of the facial nerve in two structures of the middle ear: the cochleariform process and the tympanic portion of the facial nerve. We prospectively evaluated 32 patients who underwent surgical facial nerve exploration via the middle fossa approach. Our goal was to determine the incidence of intraoperative difficulties and complications; we found none, and hearing levels could not be maintained in only one of the 32 patients. Our technique allowed us to decompress the first genu and the labyrinthine segment of the nerve. It also allowed us to reach and manipulate its tympanic segment in a very short amount of surgical time.