Secondary Logo

Institutional members access full text with Ovid®

Cochlear Implantation in Adults With Asymmetric Hearing Loss: Benefits of Bimodal Stimulation

van Loon, Maarten Caspar*,†; Smits, Cas*,†; Smit, Conrad F.*; Hensen, Erik F.*; Merkus, Paul*,†

doi: 10.1097/MAO.0000000000001418

Objective: This study addresses the outcome of cochlear implantation in addition to hearing aid use in patients with asymmetric sensorineural hearing loss.

Study Design: Prospective longitudinal study.

Setting: Tertiary referral center.

Patients: Seven adults with asymmetric sensorineural hearing loss, i.e., less than 30% aided speech recognition in their worst hearing ear and 60 to 85% speech recognition in their best hearing ear. All patients had a postlingual onset of their hearing loss and less than 20 years of auditory deprivation of their worst hearing ear.

Intervention: Cochlear implantation in the functionally deaf ear.

Main Outcome Measures: Speech recognition in quiet, speech recognition in noise, spatial speech recognition, localization abilities, music appreciation, and quality of life. Measurements were performed before cochlear implantation and 3, 6, and 12 months after cochlear implantation.

Results: Before cochlear implantation, the average speech recognition of the ear fitted with a hearing aid was 74%. Cochlear implantation eventually resulted in an average speech recognition of 75%. Bimodal stimulation yielded speech recognition scores of 82, 86, and 88% after 3, 6, and 12 months, respectively. At all time intervals, bimodal stimulation resulted in a significantly better speech recognition as compared with stimulation with only hearing aid or only cochlear implant (CI). Speech recognition in noise and spatial speech recognition significantly improved as well as the ability to localize sounds and the quality of life.

Conclusion: This study demonstrated that patients are able to successfully integrate electrical stimulation with contralateral acoustic amplification and benefit from bimodal stimulation. Therefore, we think that cochlear implantation should be considered in this particular group of patients, even in the presence of substantial residual hearing on the contralateral side.

*Department of Otolaryngology–Head and Neck Surgery, Section Ear & Hearing, VU University Medical Center

The EMGO Institute for Health and Care Research, VU University, Amsterdam, the Netherlands

Address correspondence and reprint requests to Maarten Caspar van Loon, M.D., Department of Otolaryngology–Head and Neck surgery, VU University Medical Center, KNO ZH 1d-114, PO Box 7057, 1007 MB Amsterdam, the Netherlands; E-mail:

Parts of this manuscript were presented at the 13th International Conference on Cochlear Implants and other Implantable Auditory Technologies, June 18–21, 2014, Munich, Germany and the 12th European Symposium on Pediatric Cochlear Implants, June 18–21, 2015, Toulouse, France.

Conflicts of Interest: This research was financially supported by Advanced Bionics® (Advanced Bionics, Valencia, CA).

Copyright © 2017 by Otology & Neurotology, Inc. Image copyright © 2010 Wolters Kluwer Health/Anatomical Chart Company