Preservation of residual hearing in cochlear implanted patients

Aim of this study is to investigate the preservation of residual hearing after the cochlear implant surgery. Lahore and Peshawar during the period 2001 to 2007. Eighteen patients out of an overall of 150 subjects, who underwent Cochlear Implant surgery in Lahore and Peshawar during the period 2001 to 2007, were enrolled for this study. Hearing threshold has been measured in this group of patients following cochlear implantation with Medel Combi 40+ device for the last six years. The assessment was carried out within the first post-operative month as well as at later stage, between six and 72 months, post-operatively. All Eighteen patients in our cochlear implant program who could give good pure tone audiometry results used hearing aids before implantation. The pure tone acoustic thresholds at 250, 500, 1000, 2000 and 4000 Hz were obtained using the standard audiometrical procedures before and after cochlear implantation. Hearing preservation could be achieved in 16/18 patients [86%]. In two patients partial preservation was possible [14%]. These results indicate that it is possible to partially preserve residual hearing during cochlear implant surgery