The hearing benefit of cochlear implantation for individuals with unilateral hearing loss, but no tinnitus

Abstract

Conclusion: Cochlear implants improve the hearing abilities of individuals with unilateral hearing loss and no tinnitus. The benefit is no different from that seen in patients with unilateral hearing loss and incapacitating tinnitus.

Objective: To evaluate hearing outcomes after cochlear implantation in individuals with unilateral hearing loss and no tinnitus and compare them to those obtained in a similar group who had incapacitating tinnitus.

Methods: Six cases who did not experience tinnitus before operation and 15 subjects with pre-operative tinnitus were evaluated with a structured interview, a monosyllabic word test under difficult listening situations, a sound localization test, and an APHAB (abbreviated profile of hearing aid benefit) questionnaire.

Results: All subjects used their cochlear implant more than 8 hours a day, 7 days a week. In ‘no tinnitus’ patients, mean benefit of cochlear implantation was 19% for quiet speech, 15% for speech in noise (with the same signal-to-noise ratio in the implanted and non-implanted ear), and 16% for a more favourable signal-to-noise ratio at the implanted ear. Sound localization error improved by an average of 19°. The global score of APHAB improved by 16%. The benefits across all evaluations did not differ significantly between the ‘no tinnitus’ and ‘tinnitus’ groups.

Keywords:

• Cochlear implant
• unilateral hearing loss
• speech comprehension
• hearing outcomes
• localization
• self-rated hearing difficulty

Acknowledgements

The authors thank Andrew Bell for comments on this article.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

The work was supported by the Polish National Science Centre, decision no. DEC-2013/09/B/ST7/04213.