Otoacoustic emissions in hearing screening in children

Abstract

Prevention of the consequences of hearing loss can be accomplished by early hearing screening of the cochlear function in newborus, but also with continuous hearing screening in the early childhood. The aim of this study was to investigate the reliability and feasibility of otoacoustic emissions (OAE) in hearing screening in children, evaluate the frequency and type of hearing loss and determine etiological factors of these losses. In the study, 133 children, aged 2 to 7.5 years, were tested on both ears with transient evoked otoacoustic emissions (TEOAE) and distortion-product otoacoustic emissions (DPOAE). Before screening tests all children had undergone otoscopic examination. If children had not passed either or both hearing screening tests and/or abnormal otoscopic findings in at least one ear, audiological evaluation was scheduled to confirm or exclude hearing loss. Eighty-five percent of children passed the hearing and otoscopic screening bilaterally. For additional audiologic tests 15% of children were referred. Agreement between otoscopic examination and screening tests was very good (agreement for TEOAE 95%, for DPOAE 93%). The results showed that normal tympanograms were very likely to be associated with normal screening tests. Sensitivity of TEOAE test was 94.12%, specificity 78.95%, while DPOAE sensitivity was 87.50% and specificity 75%. Hearing loss was found in 6.76% of the cases, conductive in 6.01% and sensorineural in 0.75%. Conductive hearing loss was a consequence of chronic otitis media with effusion in 25% of the cases, and a consequence of adhesive process in the middle ear in 8.33% of cases. Sensorineural hearing loss was a consequence of using ototoxic medications. TEOAE and/or DPOAE tests are reliable, noninvasive, and feasible methods for hearing screening in childhood.