Hearing loss in high-risk neonates — structured oral (viva)

Branch 1 — Screening rationale

Examiner: "Why was this infant screened with AABR rather than otoacoustic emissions?" Candidate: Automated auditory brainstem response was used because the NICU population carries the highest burden of auditory neuropathy spectrum disorder. Otoacoustic emissions test only the cochlear outer hair cells and return a normal result in auditory neuropathy, where the cochlea is intact but the nerve or brainstem misfires. AABR tests the entire pathway from sound to brainstem and therefore detects auditory neuropathy, which is why it is the mandated screen for the NICU infant. ^{[1] [2]}

Examiner: "How do you interpret a bilateral refer?" Candidate: A refer means the screen did not detect a clear brainstem response in either ear. It is not a diagnosis of hearing loss — a proportion of refers reflect transient causes such as middle-ear fluid or ambient noise. The protocol is to repeat the screen once, and if it refers again, to refer for a full diagnostic assessment. The priority is to ensure the infant is not lost to follow-up, because loss to follow-up is the commonest failure of the pathway. ^[1]