1. Department of Diagnostic and Interventional Radiology, Helios Klinikum Krefeld, Krefeld, Germany
2. Faculty of Health, School of Medicine, University Witten/Herdecke, Witten, Germany
3. Department of Diagnostic and Interventional Radiology, HELIOS University Hospital Wuppertal, Wuppertal, Germany
4. Heart Centre Niederrhein, Department of Cardiology, Helios Clinic Krefeld, Krefeld, Germany
5. Klinik und Poliklinik für Neurologie, University Hospital Bonn, Bonn, Germany
6. Department of Radiology and Neuroradiology, Klinikum Dortmund, Dortmund, Germany