1 University of Cologne, Medical Faculty, Department of Otorhinolaryngology, Head and Neck Surgery, Cologne, Germany. Electronic address: kevin.hansen@uk-koeln.de.
2 University of Cologne, Medical Faculty, Department of Otorhinolaryngology, Head and Neck Surgery, Cologne, Germany. Electronic address: antonia.nolte@uk-koeln.de.
3 University of Cologne, Medical Faculty, Department of Otorhinolaryngology, Head and Neck Surgery, Cologne, Germany. Electronic address: jens.klussmann@uk-koeln.de.