A 52-year-old man presents with a 6-month history of low-frequency roaring tinnitus in the left ear, accompanied by progressive hearing loss, fullness in the ear, and episodic vertigo. Audiometry shows a characteristic low-frequency sensorineural hearing loss (bone conduction better than air conduction at 500 Hz). Caloric testing is normal. What is the most likely diagnosis?

Explanation

## Clinical Diagnosis: Ménière's Disease ### Key Diagnostic Triad **Key Point:** Ménière's disease classically presents with the triad of: 1. Episodic vertigo (rotatory, severe, lasting hours to days) 2. Fluctuating sensorineural hearing loss (typically **low-frequency** initially) 3. Tinnitus and aural fullness ### Audiometric Pattern **High-Yield:** The characteristic audiometric finding in early Ménière's disease is **low-frequency sensorineural hearing loss** (500–2000 Hz), which distinguishes it from noise-induced or age-related hearing loss (which typically affects high frequencies first). This patient's bone conduction being better than air conduction at 500 Hz indicates sensorineural loss (not conductive). ### Pathophysiology Ménière's disease results from endolymphatic hydrops—abnormal accumulation of endolymph in the cochlea and vestibule. This causes: - Cochlear symptoms: low-frequency tinnitus and hearing loss - Vestibular symptoms: episodic vertigo with normal caloric testing (peripheral, not central) - Aural fullness from increased pressure ### Diagnostic Criteria (Modified American Academy of Otolaryngology) | Criterion | Finding in This Case | |-----------|----------------------| | Vertigo episodes | Present (episodic) | | Hearing loss | Present (low-frequency SNHL) | | Tinnitus | Present (roaring, low-frequency) | | Aural fullness | Present | | Caloric testing | Normal (rules out central cause) | | Duration | 6 months (supports diagnosis) | **Clinical Pearl:** The **roaring quality** of tinnitus in Ménière's is often described as a low-pitched, ocean-wave-like sound, contrasting with the high-pitched tinnitus of acoustic neuromas or presbycusis. ### Why Caloric Testing Is Normal Caloric testing assesses horizontal semicircular canal function. In Ménière's disease, the endolymphatic hydrops affects the entire labyrinth but does not cause a fixed vestibular deficit; therefore, caloric responses remain **symmetrical and normal** until late-stage disease. This distinguishes it from vestibular neuritis or acoustic neuroma, which would show caloric asymmetry. **Mnemonic:** **VHAF** = Vertigo, Hearing loss, Aural fullness, Fluctuating (all four present in Ménière's).