1. Department of General, Visceral, and Transplantation Surgery, Hospital of the LMU Munich, Marchioninistr. 15, D-81377 Munich, Germany
2. Department of Otolaryngology, Klinikum Rechts der Isar, Technical University of Munich, Ismaninger Str. 22, D-81675 Munich, Germany
3. Department of Orthopedic Surgery, Hospital of the LMU Munich, Marchioninistr. 15, D-81377 Munich, Germany
4. Department of Clinical Radiology, Hospital of the University of Munich, Marchioninistr. 15, D-81377 Munich, Germany