Stefan B Schäfer1, Ilse Roswag2, Gabriele A Krombach2. 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.