A 42-year-old woman presents to the ENT clinic with a 6-month history of episodic vertigo lasting 20–30 minutes, associated with tinnitus and a sensation of fullness in the left ear. During the last episode 2 days ago, she experienced sudden sensorineural hearing loss at low frequencies (500–2000 Hz) on audiometry. Between episodes, hearing partially recovers. She denies recent head trauma or ototoxic drug exposure. Caloric testing shows reduced response on the left. What is the most likely diagnosis?

Explanation

## Clinical Diagnosis: Meniere Disease ### Key Diagnostic Triad **Key Point:** Meniere disease is characterized by the classic triad of **episodic vertigo, fluctuating sensorineural hearing loss, and tinnitus**, with or without aural fullness. ### Clinical Features Matching This Case | Feature | Finding in Case | Meniere Significance | |---------|-----------------|---------------------| | **Vertigo** | Episodic, 20–30 min | Typical duration: 20 min–several hours | | **Hearing Loss** | Fluctuating, low-frequency, recovers between episodes | Pathognomonic: reversible early, permanent later | | **Tinnitus** | Present | Occurs in ~90% of cases | | **Aural Fullness** | Reported | Sensation of pressure/fullness in affected ear | | **Caloric Response** | Reduced on affected side | Indicates vestibular involvement | ### Pathophysiology 1. **Endolymphatic hydrops** — abnormal accumulation of endolymph in the membranous labyrinth 2. **Rupture of Reissner's membrane** during acute episodes → mixing of endolymph and perilymph 3. **Low-frequency hearing loss** — cochlear hydrops affects basal turn first (paradoxically low frequencies affected early) 4. **Fluctuating pattern** — hearing recovers as hydrops resolves between attacks ### Diagnostic Criteria (Modified Committee on Hearing and Equilibrium) **High-Yield:** Certain diagnosis requires: - Episodic vertigo (spontaneous, not positional) - Audiometrically documented sensorineural hearing loss (at least once) - Tinnitus or aural fullness - Other causes excluded ### Investigations Supporting Diagnosis - **Audiometry**: Sensorineural pattern, often low-frequency (500–2000 Hz) in early stages - **Caloric test**: Reduced vestibular response on affected side (as in this case) - **Electrocochleography (ECoG)**: Elevated summating potential/action potential ratio (>0.5) — most specific - **MRI**: Excludes retrocochlear pathology (vestibular schwannoma); may show endolymphatic hydrops on high-resolution sequences **Clinical Pearl:** The **fluctuating hearing loss that partially recovers between episodes** is the key distinguishing feature from other causes of vertigo and hearing loss. ### Management Approach ```mermaid flowchart TD A[Meniere Disease Suspected]:::outcome --> B[Confirm with Audiometry + Caloric Test]:::action B --> C{Frequency of Attacks?}:::decision C -->|Infrequent| D[Conservative: Salt restriction, Diuretics]:::action C -->|Frequent/Disabling| E[Intratympanic Gentamicin or Steroids]:::action E --> F{Response?}:::decision F -->|Inadequate| G[Endolymphatic Sac Decompression or Labyrinthectomy]:::action F -->|Good| H[Continue Medical Management]:::action ``` **Mnemonic:** **VOMIT** = **V**ertigo, **O**tologic symptoms (tinnitus/fullness), **M**embranous labyrinth hydrops, **I**ntermittent/episodic, **T**reatment (salt restriction, diuretics)