1. University Hospital for Urology, Klinikum Oldenburg, School of Medicine and Health Sciences, Carl von Ossietzky University, Oldenburg, Germany
2. Department of Urology, HELIOS Hospital, Bad Saarow, Germany
3. Department of Urology, Lukas Hospital, Neuss, Germany
4. University Hospital for Anaesthesiology, Klinikum Oldenburg, School of Medicine and Health Sciences, Carl von Ossietzky University, Oldenburg, Germany