Benefits of unilateral cochlear implantation in adults with asymmetric hearing loss: Audiologic and patient-related outcome measures

Abstract

PurposeTo investigate the benefits of cochlear implantation in adults with single-sided deafness (SSD) and asymmetric hearing loss (AHL). Study designProspective within-subjects repeated-measures. SettingTwo tertiary cochlear implant centers. PatientsFourteen adults with severe-to-profound sensorineural hearing loss in the worse hearing ear and up to moderate SNHL in the better hearing ear. InterventionCochlear implantation in the worse hearing ear. Main outcome measuresConsonant-nucleus-consonant (CNC) test, AzBio sentence test in noise, and lateralization testing were conducted preoperatively and at 3-, 6-, and 12-months post-activation. Patient-related outcomes were measured using the Speech, Spatial, and Qualities of Hearing Scale and Glasgow Benefit Inventory. Tinnitus Handicap Inventory was administered to subjects with tinnitus. ResultsMean length of hearing loss in the worse hearing ear was 3.5 years. The mean CNC change scores from baseline were 54.8, 55.9, and 58.9 percentage points at 3-, 6-, and 12-months (p < 0.001). AzBio sentence test in noise demonstrated improved scores in all spatial configurations, although statistically significant in S0N0 (speech front, noise front) only. Lateralization testing showed significant improvement of 22.9, 24.5, and 24.0 percentage points at 3-, 6-, and 12 months post-activation (p = 0.002). All patient-related outcome measures revealed significant improvement. ConclusionThis study demonstrates improved speech perception in noise, sound lateralization, quality of life, and reduction in tinnitus perception in adults with SSD/AHL who undergo cochlear implantation. Our results add to the growing body of evidence that cochlear implant should be offered to this population.