Original Article

Can the use of the CROS system provide head shadow effect contribution to unilateral Cochlear Implant Users?

Ana Cristina Hiromi Hoshino; Maria Valéria Schmidt Goffi-Gomez; Paola Angelica Samuel Sierra; Smita Agrawal; Carina Rodriguez; Ana Claudia Martinho de Carvalho; Robinson Koji Tsuji

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Purpose: The aim of this study was to evaluate the contribution of the CROS system on the head shadow effect in unilateral implant users. Methods: Prospective cross-sectional study, approved by the ethics committee under protocol 2.128.869. Eleven adults with post-lingual deafness users of unilateral Advanced Bionics CI were selected. Speech recognition was evaluated with recorded words presented at 65dBA at 0o azimuth and at 90o on the side contralateral to the CI, with noise at 55dBA, using CI alone and CI + CROS system. The results were analyzed using paired t-test with a 0.05 alpha. Results: The mean speech recognition scores were significantly better with CI + CROS in relation to the condition of CI alone (p <0.05, p <0.005 and p <0.005 respectively). In the presentation at 0o azimuth, no significant differences were found. Conclusion: Users of unilateral CI without useful residual hearing for the use of hearing aids or unable to undergo bilateral surgery can benefit from the CROS device for speech recognition, especially when the speech is presented on the side contralateral to the CI.


Unilateral Cochlear Implant; Contralateral Routing of Signal; Speech Clarity; Ease of Listening; Head-shadow


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