1. Department of Diagnostic and Interventional Radiology, HELIOS Hospital Krefeld, Germany
2. School of Medicine, University Witten Herdecke Faculty of Health, Witten, Germany
3. Department of Diagnostic and Interventional Radiology, HELIOS University Hospital Wuppertal, Germany
4. Department of Diagnostic and Interventional Radiology, University Hospital of Düsseldorf, Dusseldorf, Germany
5. Head Office, German Roentgen Society, Berlin, Germany
6. Department of Interventional Radiology, Technical University of Munich, Munchen, Germany