1. Department of Interventional Radiology and Neuroradiology, Neurocenter Solingen, radprax St. Lukas Hospital, Solingen, Germany
2. School of Medicine, Department of Health, Witten/Herdecke University, Witten, Germany
3. Diagnostic and Interventional Radiology and Neuroradiology, Alfried-Krupp-Hospital, Essen, Germany
4. Department of diagnostic and interventional Radiology, Helios Universitiy Hospital, Wuppertal, Germany