1. Interdisciplinary Endoscopy, Medical Department I, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany
2. Elblandclinic, Medical Department II, Riesa, Germany
3. Institute of Cytology, Hannover, Germany
4. Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany
5. Department of Oral and Maxillofacial Surgery, University Hospital Schleswig-Holstein, Campus Kiel, Kiel, Germany