A 14-month-old referred for delayed speech shows present distortion-product and transient otoacoustic emissions bilaterally, but click-evoked ABR demonstrates only a small Wave I with absent later waves, and speech perception is far worse than the behavioural thresholds suggest. The most likely diagnosis is:

• A Bilateral severe cochlear sensorineural hearing loss
• B Bilateral cochlear aplasia
• C Bilateral otitis media with effusion
• D Auditory neuropathy spectrum disorder ✓

Explanation

Preserved otoacoustic emissions prove that outer hair cells are functioning, while absent or severely disrupted ABR waves beyond Wave I indicate failure of neural synchrony in the auditory nerve and brainstem pathways. This dissociation of normal cochlear function from disordered neural conduction is the defining picture of auditory neuropathy spectrum disorder, seen with OTOF mutations, kernicterus and prematurity. Severe cochlear loss abolishes emissions, and effusion alters middle ear mechanics, reducing emissions.

Reference: Katz, Handbook of Clinical Audiology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.