Received: 9 April 2019
Accepted: 9 July 2019
First Online: 12 July 2019
Ethics approval and consent to participate
: The study protocol was in line with the Declaration of Helsinki and was approved by the institutional review board of the Medical University of Vienna. All patients gave their written informed consent.
: All authors of this paper have read and approved the final version submitted.
: The authors declare that they have no competing interests.