Speech Perception Ability and Subjective Satisfaction After Upgrade of Speech Processor in Cochlear Implantation

Objective: Cochlear implant (CI) users face the decision of whether to upgrade to a new sound processor (SP) with technological advances. We wanted to assess the changes of speech perception ability and aided hearing thresholds as well as subjective satisfaction after upgrade to a new SP. Methods: Fifty-five patients who have used CI for 10 years or more and upgraded to a new SP were enrolled. Word recognition scores were assessed before the upgrade and compared to those assessed 1 year after the upgrade to the Nucleus 7 SP. Changes of aided hearing thresholds and C- and T-levels were analyzed. Results: Previous SPs were 3G in 5, Freedom in 40, N5 in 24, and N6 in 6. Speech perception remained relatively unaffected by SP upgrade. The C- and T-levels increased after SP upgrading and the aided thresholds with previous generation SPs were higher than those 1 year after SP upgrading at all frequencies. In questionnaires, subjects felt that there was a definite subjective benefit to upgrading while most (60%) felt no difference regarding the communication in noise. Conclusions: Speech perception remained similar, but there were improved hearing sensitivity and better satisfaction after SP upgrade.