Auditory Neuropathy/Dys-Synchrony: After the Diagnosis, then What?

ABSTRACT

Neither auditory brainstem response (ABR) nor otoacoustic emissions (OAEs) are objective hearing tests, nor are their results always mutually consistent in any one patient. Therefore, it is quite possible for a patient to have normal emissions but absent or grossly abnormal ABR and behavioral audiograms that are inconsistent with either test. These patients, who may constitute as much as 10% of the diagnosed deaf population, are the subject of this article. To diagnose as many as possible properly from the onset, we urge triage (sorting or preselection by a system of priorities designed to maximize the effectiveness of treatment or outcome) using (1) tympanometry, (2) middle ear muscle reflexes, and (3) OAEs. Early diagnosis is essential because after either hearing aid use or the passage of time these patients often lose their OAEs and become almost indistinguishable from patients with ordinary deafness. Because auditory verbal therapy and hearing aids are rarely if ever successful with these patients until after cochlear implantation, it is essential to design intervention and interpret their audiograms physiologically rather than in conventional articulation index terms. This article offers management suggestions based on our experiences with close to 200 patients and their families. These suggestions include cued speech and baby signs for newborns. Cued speech gives them access to their parents' vocabulary and language, and the baby signs give them vocabulary to express needs and wants and remain linguistically attached. Then, if they are among the 93% of children who stay impaired, we have seen that cochlear implants are quite effective.

KEYWORDS

Auditory brainstem response (ABR) - otoacoustic emissions (OAEs) - reversing click polarity - cochlear microphonics (CM) - latency-intensity function

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