A 30-year-old man develops an acute left lower motor neuron facial palsy. On history he complains that sounds, especially his own voice, seem uncomfortably loud on the left side. This symptom localises the lesion to a site:

• A Distal to the nerve to stapedius
• B At the stylomastoid foramen
• C In the internal auditory meatus only
• D Proximal to the origin of the nerve to stapedius ✓

Explanation

Hyperacusis results from paralysis of the stapedius muscle, which normally damps ossicular movement. The stapedius branch arises from the descending (mastoid) segment of the facial nerve, so hyperacusis means the lesion lies proximal to that branch, typically at or above the pyramidal turn. Lesions at the stylomastoid foramen or distally spare the stapedius branch, so there would be no hyperacusis, eliminating options A and B.

Reference: Dhingra's Diseases of Ear, Nose and Throat, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.