1. Department of Otorhinolaryngology, Head and Neck Surgery, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität and Berlin Humboldt Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany
2. Department of Otorhinolaryngology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany