1 Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Marburg, Philipps-Universität Marburg, Marburg, Germany. Electronic address: boris.stuck@uk-gm.de.
2 Smell and Taste Clinic, Department of Otorhinolaryngology, Technische Universität Dresden, Dresden, Germany.
3 Department of Otorhinolaryngology, Head and Neck Surgery, Kiel University, University Medical Centre Schleswig-Holstein, Kiel, Germany.
4 Department of Otorhinolaryngology, Regensburg University Hospital, Regensburg, Germany.