During surgery for cholesteatoma, the facial nerve is identified in its tympanic (horizontal) segment. The landmark used to identify the tympanic segment of the facial nerve in the middle ear is:

• A Pyramid eminence
• B Processus cochleariformis (cochleariform process) ✓
• C Round window niche
• D Posterior semicircular canal prominence

Explanation

The processus cochleariformis (cochleariform process) is the most reliable landmark for the tympanic segment of the facial nerve. The nerve runs just superior and posterior to this process as it hooks around to supply the tensor tympani and then continues posteriorly. The tympanic segment runs from the geniculate ganglion to the second genu (where it turns inferiorly as the mastoid segment). The lateral semicircular canal prominence overlies the aditus and is useful for the mastoid segment. The pyramid houses the stapedius tendon.

Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.