C Neubauer1, H Gruber2, J Bäuerle3, K Egger4. 1. Department of Radiology, University Medical Center Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany. 2. Department of Radiology, Innsbruck Medical University, Anichstraße 35, 6020, Innsbruck, Austria. 3. Department of Neurology, University Medical Center Freiburg, Breisacher Str. 64, 79106, Freiburg, Germany. 4. Department of Neuroradiology, University Medical Center Freiburg, Breisacher Str. 64, 79106, Freiburg, Germany. karl.egger@uniklinik-freiburg.de.