Received: 10 October 2017
Accepted: 10 July 2018
First Online: 6 September 2018
Ethics approval and consent to participate
: The study was conducted in accordance with the Declaration of Helsinki [CitationRef removed] and the ICH Harmonised Tripartite Guideline for Good Clinical Practice (CPMP/ICH/135/95) [CitationRef removed]. Before enrolment of the first patient, the trial was approved by the local ethics commission of the Department of Otolaringology of Ivano-Franskivsk National Medical University (protocol No. 26 dd. November 26, 2015), Ukraine and received a favourable opinion by the ethics committee competent for the coordinating investigator. Written informed consent was received from all legal representatives of the patients prior to any study related measures.
: Not applicable.
: The trial was carried out on the initiative of the authors.The author received an honorarium for preparing the manuscript based on the results of this study. The authors state that they have no competing interests.
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