Which of the following findings on audiometry is PATHOGNOMONIC for sensorineural hearing loss?

Explanation

## Audiometric Findings in Sensorineural Hearing Loss **Key Point:** In sensorineural hearing loss, BOTH air conduction and bone conduction thresholds are elevated EQUALLY, with **no air-bone gap** (gap ≤ 10 dB). This is the pathognomonic audiometric finding. ### Pathophysiology Sensorineural hearing loss results from dysfunction of the cochlea, auditory nerve, or central auditory pathways. Both air and bone conduction pathways converge at the cochlea, so cochlear/neural damage affects both equally. ### Audiometric Comparison Table | Feature | Conductive Loss | Sensorineural Loss | |---------|-----------------|--------------------| | **Air conduction threshold** | Elevated | Elevated | | **Bone conduction threshold** | Normal | Elevated | | **Air-bone gap** | > 10 dB (air worse) | ≤ 10 dB (absent/minimal) | | **Rinne test** | Bone > Air (on affected side) | Air > Bone (or both abnormal) | | **Weber test** | Lateralizes to affected ear | Lateralizes to better ear | **High-Yield:** **No air-bone gap = sensorineural loss**. An air-bone gap > 10 dB indicates conductive pathology. **Mnemonic:** **SNHL = SAME THRESHOLD** (air and bone both bad equally). **Clinical Pearl:** The air-bone gap is the single most useful audiometric parameter to differentiate conductive from sensorineural hearing loss. A gap > 10 dB always indicates conductive loss; absence of gap indicates sensorineural loss (or mixed loss with sensorineural predominance).