Aligning Hearing Aid and Cochlear Implant Improves Hearing Outcome in Bimodal Cochlear Implant Users

Patients with unilateral deafness and residual hearing on the contralateral ear can benefit from a cochlear implant (CI) on one side and a hearing aid (HA) on the other. However, hearing improvement among these patients is heterogenous. Interindividual differences in bimodal benefit may be caused by a mismatch of CI and HA. The aim of this study was to clinically apply a HA fitting strategy and to evaluate hearing outcome with and without a dedicated bimodal fitting formula.

Prospective non-randomized study.

Tertiary referral center.

Twelve patients using a CI processor and a conventional HA were enrolled. Before and after the new HA had been adjusted to the patient and linked to the CI, pure-tone audiometry and localization tests were performed. Speech perception was determined in quiet and noise. Tests were repeated after 6 and 12 weeks. To evaluate the subjective listening comfort two questionnaires (Oldenburg Inventory and HISQUI19) were assessed.

Therapeutic.

Word recognition in quiet, sentence recognition in noise. Speech perception in noise improved significantly: directed suppression of noise helped to segregate the target speech signal from a mixture of sounds or competing speakers. Evaluation of the questionnaires revealed a positive subjective hearing experience compared with patients' initial settings of the devices.

By linking CI and HA hearing and speech perception can be improved. However, good counselling at the outset is essential to obtain enhanced outcome.