1. Department of Otolaryngology, Head and Neck Surgery, Medical Faculty Mannheim, University of Heidelberg, D‑68167 Mannheim, Germany
2. Department of Otorhinolaryngology, Head and Neck Surgery, Marburg University Hospital, Philipps‑University Marburg, D-35043 Marburg, Germany
3. HNO‑Zentrum Oldenburger M�nsterland, D‑49661 Cloppenburg, Germany
4. Department of Anesthesiology and Intensive Care Medicine, St. Josefs‑Hospital, D‑49661 Cloppenburg, Germany