1. Department of Otorhinolaryngology, University of Regensburg, 93053 Regensburg, Germany
2. Department of Psychiatry and Psychotherapy, University of Regensburg, 93053 Regensburg, Germany
3. Clinic Lech-Mangfall, 83734 Agatharied, Germany
4. Department of Otorhinolaryngology, University of Zurich, 8091 Zürich, Switzerland