A Nordic cohort study on cochlear implants and binaural hearing in single-sided deafness

BackgroundSingle-sided deafness (SSD) is associated with impaired speech recognition in noise, reduced sound localization, decreased quality of life (QoL), and often bothersome tinnitus. Cochlear implantation has emerged as a treatment option for selected adults with SSD.ObjectivesTo evaluate the effects of cochlear implantation on speech recognition in noise, sound localization, QoL, and tinnitus in adults with SSD.Material and Methods This retrospective cohort study with prospective follow-up included 12 adults with SSD who underwent cochlear implantation between 2015 and 2024 at a tertiary referral center. Assessments included the Danish Sentence Test (DAST), sound localization testing, and patient-reported outcome measures. Speech reception thresholds (SRTs), localization accuracy (RMSE), QoL (NCIQ), and tinnitus burden (THI) were evaluated.Results Cochlear implantation significantly improved speech recognition in the head shadow condition, whereas no significant improvements were observed for binaural squelch or summation. Sound localization accuracy improved significantly. Total NCIQ and THI scores also improved significantly.Conclusions and Significance Cochlear implantation improved speech recognition in noise, sound localization, quality of life, and tinnitus burden in adults with SSD, supporting its use as an effective treatment option for selected patients.