Results of cochlear implantation in 25 adult patients with profound hearing loss between 70 and 90 dBHL

Abstract

The aim of this study is to determine the efficacy of cochlear implantation in patients with residual hearing loss. The level of hearing loss in postlingually deaf adults who had cochlear implantation at Miyazaki University hospital between 2009 and 2019 were classified according to pure-tone averages as bilateral severe (group A), severe in the implanted ear and profound in the other (group B), profound in the implanted ear and severe in the other (group C), and bilaterally profound (group D). There were no significant differences in the speech discrimination score among the four groups. Cochlear implantation had a beneficial effect on speech recognition, regardless of the hearing status of the implanted ear. All individuals except for one chose to achieve binaural hearing using a cochlear implant with a contralateral hearing aid in groups A and C. Patients in group A underwent cochlear implantation for reasons such as acute hearing loss or old age. Patients in group B selected implantation in the ear with severe hearing loss because of a long duration of hearing loss in the profound ear or a hearing aid in the severely impaired ear being useless. While implantation in the better hearing ear makes it difficult to use a hearing aid, it is an option in patients with asymmetrical hearing loss, depending on the duration of hearing loss or age. We should therefore provide the patient with the best opportunity to achieve binaural hearing.