A 45-year-old man with a 10-year history of progressive bilateral hearing loss develops sudden profound sensorineural hearing loss in the left ear following minor head trauma. CT temporal bone reveals spongiotic lucency around the anterior margin of the oval window. What is the pathological diagnosis?
- A Labyrinthine fistula from cholesteatoma eroding the lateral semicircular canal
- B Otospongiosis with cochlear otosclerosis involving the otic capsule ✓
- C Menière disease with endolymphatic hydrops
- D Ototoxic damage from aminoglycosides
Correct answer: B. Otospongiosis with cochlear otosclerosis involving the otic capsule
Explanation
The CT finding of spongiotic lucency at the fissula ante fenestram (anterior to the oval window) is pathognomonic for otosclerosis. When the disease extends into the otic capsule (cochlear otosclerosis), the inner ear becomes vulnerable to trauma, causing sudden SNHL. Cholesteatoma fistula typically involves the lateral semicircular canal, not the oval window.
Reference: Cummings Otolaryngology: Head and Neck Surgery, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.