During tympanoplasty, the surgeon views the medial wall of the middle ear. The rounded bulge between the fenestra vestibuli above and the fenestra cochleae below is formed by which structure?

• A Processus cochleariformis
• B Canaliculus for the chorda tympani
• C Prominence of the lateral semicircular canal
• D Basal turn of the cochlea ✓

Explanation

The promontory is the rounded elevation on the medial wall of the middle ear produced by the first (basal) turn of the cochlea. It lies covered by mucosa overlying the tympanic plexus (Jacobson's nerve, from IX). Above it is the oval window with the facial canal prominence, below and behind is the round window. The processus cochleariformis is anterior near the tensor tympani tendon, and the lateral canal bulge is in the aditus region above the facial canal.

Reference: Gray's Anatomy, 42nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.