Auditory neuropathy/dys‐synchrony: Diagnosis and management

TLDR

Auditory brainstem responses and otoacoustic emissions are objective measures of auditory function, yet patients can have normal OAEs with abnormal ABRs and inconsistent audiograms, representing up to 10 % of the deaf population diagnosed with auditory neuropathy/dys‑synchrony. The study aims to diagnose auditory neuropathy/dys‑synchrony accurately by recording ABRs to condensation and rarefaction clicks to separate cochlear microphonics from neural responses. Management recommendations involve visual language exposure via American Sign Language, Cued Speech, or baby signs, coupled with close patient monitoring.

Abstract

Auditory brainstem responses (ABRs) and otoacoustic emissions (OAEs) are objective measures of auditory function, but are not hearing tests. Normal OAEs reflect normal cochlear outer hair cell function, and an ABR indicates a synchronous neural response. It is quite possible for a patient to have normal OAEs but absent or grossly abnormal ABR and a behavioral audiogram that is inconsistent with either test. These patients, who may constitute as much as 10% of the diagnosed deaf population, have auditory neuropathy/dys-synchrony (AN/AD). To diagnose AN/AD accurately, ABRs are obtained in response to condensation and rarefaction clicks to distinguish cochlear microphonics (CM) from neural responses. Appropriate management is confounded by variation among patients and changes in auditory function in some patients over time. Recommendations for management include visual language exposure through methods such as American Sign Language (ASL), Cued Speech, or baby signs, and closely following patients.