ABSTRACT
Objective To study the influence of cochlear implantation on residual hearing in children .Methods Behavioral audiometry were performed pre -implant and 3~21 months post -implant on thirty -four cochlear implant recipients with severe to profound hearing loss .According to follow -up time ,they were divided into 2 groups which were Group A(3~12 months ,21 cases) and Group B(≥13 months ,13 cases) .The thresholds at 250 Hz ,500 Hz ,1 000 Hz and 2 000 Hz were analyzed .Results There were 25 out of 34 patients (73 .53% ) had partial residual hearing after cochlear implantation .Comparing to the hearing loss pre -operation and post -operation , which were most obvious at 500 Hz ,followed by 250 Hz ,1 000 Hz ,2 000 Hz (P<0 .05) ,and there were significant different among different frequencies .There was significant difference at different frequencies at hearing loss thresh-olds only in Group A .But there was no significant difference in Group B .With the prolonged time after the cochlear implantation ,residual hearing at all frequencies showed a trend of recovery .Conclusion The residual hearing could be partial preserved after cochlear implant in pediatric patients with severe to profound hearing impaired ,the residu-al hearing at lower frequencies (250 Hz ,500 Hz) were less affected than those at higher frequencies .With the pro-longed time after the cochlear implantation ,the residual hearing showed a certain degree of recovery .