1 Department of Radiology, University Hospital Giessen, Justus-Liebig University Giessen, Klinikstrasse 33, 35392, Giessen, Germany. Stefan.B.Schafer@radiol.med.uni-giessen.de.
2 Department of Radiology, University Hospital Giessen, Justus-Liebig University Giessen, Klinikstrasse 33, 35392, Giessen, Germany.