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Article History

Received: 3 April 2018

Accepted: 23 October 2018

First Online: 6 November 2018

Ethics approval and consent to participate

: The study protocol was approved by the Ethics Committee at the Institute of Physiology and Pathology of Hearing and every patient gave an informed consent to participate in the study.

: Not applicable.

: The authors declare that they have no competing interests.

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