Facial Nerve - Infratemporal Paths

Infratemporal Paths

Upon reaching the temporal bone, the nerve's path can be divided into the internal auditory canal, labyrinthine segment, intratympanic segment, and descending or vertical segment. The labyrinthine segment is the narrowest portion of this pathway and is described to be approximately 0.7mm in diameter. The descending segment is the area where the branches of the chorda tympani and nerve to the stapedius branch from the facial nerve. The facial nerve eventually exits via the stylomastoid foramen to enter into the parotid where it branches into its peripheral segments.