1. Second Department of Surgery, Krankenanstalt Rudolfstiftung, Vienna, Austria
2. Department of Surgery, Kaiserin-Elisabeth-Spital, Vienna, Austria
3. Department of Urology, Medical University of Vienna, Vienna, Austria
4. Department of Otorhinolaryngology, Krankenanstalt Rudolfstiftung, Vienna, Austria
5. Institute of Pharmacology, Medical University of Vienna, Vienna, Austria
6. Ear, Nose and Throat, University Hospital Graz, Department of Phoniatrics, Medical University of Graz, Graz, Austria