Article History
Received: 26 July 2018
Accepted: 29 October 2018
First Online: 21 November 2018
Ethics approval and consent to participate
: The study protocol was approved by the Institutional Review Board for Human Studies at RWTH University, Aachen, Germany (14–074), and was performed in accordance with the ethical standards laid down in the Declaration of Helsinki. Written informed consent was obtained from all patients prior to inclusion into the study.
: Not applicable.
: A discount was given for the purchase of the ENK fiberoptic atomizer from Cook medical. The funder had no role in planning or carrying out of the study. Apart from that the authors have no conflict of interest to declare.
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