During posterior tympanotomy (facial recess approach), the surgeon drills a triangle bounded laterally by the chorda tympani nerve. What forms the medial boundary of this recess?

• A Mastoid segment of the facial nerve ✓
• B Short process of the incus
• C Sinus tympani
• D Tegmen tympani

Explanation

The facial recess is bounded medially by the descending (mastoid) segment of the facial nerve, superiorly by the incus buttress near the short process of the incus, and laterally by the chorda tympani nerve. Drilling within these limits gives access to the middle ear without disturbing the ossicular chain. The sinus tympani lies medial to the facial nerve and is not part of the facial recess, which is exactly why cholesteatoma there cannot be reached through this route.

Reference: Scott-Brown's Otorhinolaryngology and Head and Neck Surgery, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.