1. Institute of Radiology and Neuroradiology, Faculty of Medicine and University Hospital, University of Cologne, Cologne, Germany
2. Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
3. Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
4. Department of Neuroradiology, University Hospital Munich (LMU), Munich, Germany