In the intratemporal course of the facial nerve, which segment contains the geniculate ganglion and gives rise to the greater petrosal nerve?
- A Meatal (canalicular) segment
- B Labyrinthine segment ✓
- C Tympanic (horizontal) segment
- D Mastoid (vertical) segment
Correct answer: B. Labyrinthine segment
Explanation
The labyrinthine segment extends from the internal auditory canal fundus to the geniculate ganglion. It is the shortest and narrowest segment of the intratemporal facial nerve. At the geniculate ganglion, the nerve makes its first genu and gives off the greater petrosal nerve, which carries parasympathetic fibers to the lacrimal gland. This segment is the site of compression in Bell's palsy.
Reference: Cummings Otolaryngology: Head and Neck Surgery, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.