A A Emara1. 1. Audiology Unit, ENT Department, Tanta University, Tanta, Egypt. Afaf_emara@hotmail.com
Abstract
INTRODUCTION: The auditory brainstem response consists of fast and slow waves. The acoustically evoked, short latency negative response is a large, negative deflection with a latency of 3 milliseconds which has been reported in patients with profound hearing loss. It may be of vestibular, particularly saccular, origin, as is the vestibular evoked myogenic potential. PURPOSE: To assess the presence of acoustically evoked, short latency negative responses in children with severe to profound sensorineural hearing loss. MATERIALS AND METHODS: Twenty-three children (46 ears) with sensorineural hearing loss underwent audiological evaluation and auditory brainstem response, vestibular evoked myogenic potential and caloric testing. RESULTS: An acoustically evoked, short latency negative response was present in 30.43 per cent of ears and absent in 69.57 per cent. Vestibular evoked myogenic potentials were recorded in all ears in the former group, but in only 53.13 per cent in the latter group. Caloric testing was normal in 82.6 per cent of the total ears tested. CONCLUSION: The presence of an acoustically evoked, short latency negative response is dependent not on residual hearing but on normal saccular function. This response can be measured in patients who cannot contract their neck muscles.
INTRODUCTION: The auditory brainstem response consists of fast and slow waves. The acoustically evoked, short latency negative response is a large, negative deflection with a latency of 3 milliseconds which has been reported in patients with profound hearing loss. It may be of vestibular, particularly saccular, origin, as is the vestibular evoked myogenic potential. PURPOSE: To assess the presence of acoustically evoked, short latency negative responses in children with severe to profound sensorineural hearing loss. MATERIALS AND METHODS: Twenty-three children (46 ears) with sensorineural hearing loss underwent audiological evaluation and auditory brainstem response, vestibular evoked myogenic potential and caloric testing. RESULTS: An acoustically evoked, short latency negative response was present in 30.43 per cent of ears and absent in 69.57 per cent. Vestibular evoked myogenic potentials were recorded in all ears in the former group, but in only 53.13 per cent in the latter group. Caloric testing was normal in 82.6 per cent of the total ears tested. CONCLUSION: The presence of an acoustically evoked, short latency negative response is dependent not on residual hearing but on normal saccular function. This response can be measured in patients who cannot contract their neck muscles.