Clinical presentation and audiologic findings in pediatric auditory neuropathy

Abstract

Aim: of the study was to rule out audiologic findings, related etiologies and its effect in pediatric patients having hearing deficits that are most likely due to a neuropathy of the eighth nerve. Study Design: Retrospective neo-natal hearing screening programme based. Subject and Methods: Subjects include 30 children aged from 0 yrs to 12 yrs, were tested with pure tone audiometry, behavioral observation audiometry, free-filed audiometry, speech audiometry, auditory brainstem response, and click evoked otoacoustic emissions. Results: Pure tone and free-field testing revealed 40 ears (66.67%, n = 60) with sloping type, sensorineural hearing loss, 20 ears (33.3%, n = 60) had flat configuration. Out of this 18 (6%, n = 30) subject showed bilateral similar configuration (either bilateral sloping type/ flat type of audiogram). Rest 12 (40%, n = 30) subject showed bilateral different pattern. 10 (33.3%, n = 30 children demonstrated fair to poor word discrimination scores and the other 2 (6.67%, n = 30) had fair to good word discrimination. For other rest of 18 (60%, n = 30) children speech test couldn't be performed because of age limit and poor speech and language development. Out of 30 subjects 28 (93.3%, n = 30) showed normal distortion product Otoacoustic emissions and 2(6.67%, n = 30) subjects showed absent emissions. Conclusions: All thirty children demonstrated absent or marked abnormalities of brainstem auditory evoked potentials which suggest cochlear outer hair cell function is normal; mostly lesion is located at the eighth nerve or beyond. Generally auditory neuropathy is associated with different etiologies and it is difficult to diagnose auditory neuropathy with single audiological test; sufficient test of battery is required for complete assessment and diagnosis of auditory neuropathy