Predictors of Early and Long-Term Sound Quality Ratings in Adult Cochlear Implant Recipients

Objective(s): To characterize the trajectory of subjective sound quality perception over time in adult cochlear implant (CI) recipients and identify predictors of early and long-term sound quality outcomes. Methods: In this retrospective analysis, 339 adult CI recipients completed the speech, spatial and qualities of hearing scale (SSQ-12) pre-operatively and at 1, 6, and 12 months post-activation. Demographic, audiometric, and electrode placement data were analyzed using linear mixed effects models to identify predictors of sound quality ratings on the SSQ-12 qualities subscale. Results: Sound quality ratings showed statistically significant improvement from pre-operative baseline to 1-month and from 1- to 6-months post-activation, with no significant change between 6- and 12-months. Better early (1-month) sound quality ratings were significantly predicted by better pre-operative sound quality ratings, better word recognition, closer modiolar distance, and a deeper insertion depth. Better long-term (6–12 month) sound quality ratings were significantly predicted by younger age, greater daily CI processor use, and better 1-month sound quality ratings. Conclusion: Perceived sound quality in CI recipients plateaued by 6 months post-activation. While electrode placement factors and better pre-op word recognition significantly predicted early sound quality outcomes, younger age and greater device use predicted better long-term sound quality ratings, highlighting opportunities for targeted intervention to optimize sound quality outcomes. Importantly, these findings underscore the need for more sensitive sound quality assessment tools to better evaluate surgical and patient factors that affect recipients' subjective auditory experiences. Level of Evidence: 4.