A 40-year-old woman presents with episodic rotatory vertigo, fluctuating left-sided hearing loss, tinnitus, and ear fullness. Audiometry during an attack shows an upward-sloping low-frequency sensorineural loss. The underlying histopathological abnormality is:

• A Loss of outer hair cells in the basal turn
• B Demyelination of the cochlear nerve
• C Endolymphatic hydrops with distension of the membranous labyrinth ✓
• D Perilymphatic fistula at the round window

Explanation

Meniere disease is defined histologically by endolymphatic hydrops: distension of the scala media due to impaired endolymph absorption, classically in the endolymphatic sac. Rupture of Reissner membrane and potassium intoxication of hair cells explain the fluctuating low-frequency SNHL. Basal turn hair cell loss characterises noise-induced and ototoxic injury, and demyelination belongs to auditory neuropathy, so options A and D are wrong.

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.