A 62-year-old man presents with progressive bilateral hearing loss over 10 years. Audiometry shows a characteristic bone conduction threshold of 45 dB HL and air conduction threshold of 65 dB HL at 2 kHz, with an air-bone gap of 20 dB. The Weber test lateralizes to the right ear. What is the most appropriate next step in management?

Explanation

## Clinical Interpretation The audiogram shows a **conductive hearing loss** pattern: - Air-bone gap of 20 dB (pathognomonic for conductive loss) - Bone conduction better than air conduction - Bilateral presentation with 10-year progression suggests **otosclerosis** (most common cause of progressive conductive hearing loss in adults) ### Key Audiometric Findings | Parameter | Finding | Significance | |-----------|---------|---------------| | Air conduction (AC) | 65 dB HL | Elevated | | Bone conduction (BC) | 45 dB HL | Relatively preserved | | Air-bone gap | 20 dB | Diagnostic of conductive loss | | Weber lateralization | Right ear | Confirms conductive loss on right (sound travels to better bone-conducted ear) | **Key Point:** An air-bone gap ≥15 dB is diagnostic of conductive hearing loss and mandates otologic evaluation to identify the structural cause. ### Management Algorithm ```mermaid flowchart TD A[Conductive hearing loss on audiometry]:::outcome --> B{Etiology identified on otoscopy?}:::decision B -->|No clear cause| C[CT temporal bone to rule out ossicular pathology]:::action B -->|Yes - cerumen/effusion| D[Conservative management or myringotomy]:::action C --> E{Ossicular fixation or discontinuity?}:::decision E -->|Fixation - likely otosclerosis| F[Offer ossiculoplasty or hearing aid]:::action E -->|Discontinuity| G[Ossiculoplasty]:::action F --> H[Audiologic follow-up]:::outcome G --> H ``` **Clinical Pearl:** Otosclerosis typically presents with: - Progressive conductive or mixed hearing loss - Bilateral involvement (70% of cases) - Carhart notch (bone conduction dip at 2 kHz) — though not always present - Female predominance (2:1) - Stapes fixation on surgery **High-Yield:** The next step in **any** conductive hearing loss is **imaging (CT temporal bone)** to identify the structural cause, followed by consideration of surgical correction (ossiculoplasty/stapedectomy) or amplification (hearing aid). Corticosteroids and antibiotics have no role in otosclerosis. **Tip:** The lateralization to the right ear in Weber test confirms the right ear has **better bone conduction** (because it's the ear with conductive loss — bone-conducted sound is not affected by middle ear pathology). This is a key diagnostic clue.