During a cortical mastoidectomy, the surgeon identifies the chorda tympani nerve. Which statement about its course and function is CORRECT?
- A It exits the facial canal at the pyramidal eminence and supplies motor fibres to tensor tympani
- B It passes through the foramen lacerum to reach the pterygopalatine ganglion
- C It crosses the medial wall of the middle ear between the incus and malleus and joins the lingual nerve in the infratemporal fossa ✓
- D It carries general sensation from the external auditory canal and concha
Correct answer: C. It crosses the medial wall of the middle ear between the incus and malleus and joins the lingual nerve in the infratemporal fossa
Explanation
The chorda tympani arises from the descending segment of the facial canal, enters the middle ear, crosses the tympanic cavity lying between the long process of the incus and the handle of malleus, exits via the petrotympanic fissure, and joins the lingual nerve in the infratemporal fossa. It carries taste from the anterior two-thirds of the tongue and secretomotor fibres to the submandibular ganglion, not motor supply to tensor tympani, which kills option A.
Reference: Gray's Anatomy for Students, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.