A 55-year-old woman has a completely dead left ear (profound sensorineural loss). Rinne test performed with a 512 Hz tuning fork on the left mastoid shows bone conduction apparently greater than air conduction. This 'false negative' Rinne occurs because:
- A The ossicular chain is fixed on that side
- B The tuning fork was applied with excessive pressure
- C Vibration conducted through the skull reaches the contralateral normal cochlea ✓
- D The external canal was occluded during testing
Correct answer: C. Vibration conducted through the skull reaches the contralateral normal cochlea
Explanation
In total or profound unilateral sensorineural loss, bone-conducted vibration bypasses the tested ear entirely and stimulates the opposite normal cochlea by transcranial crossover, so the patient reports hearing the fork on the mastoid. This mimics a conductive loss. The Weber test resolves the confusion by lateralizing to the healthy ear, confirming the loss is sensorineural rather than conductive.
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.