Stefan Weidauer1, Nadja Treusch2, Elke Hattingen3. 1. Department of Neurology, Sankt Katharinen Hospital, Teaching Hospital of the Goethe University, Seckbacher Landstraße 65, 60389, Frankfurt am Main, Germany. stefan.weidauer@sankt-katharinen-ffm.de. 2. Department of Radiology, Sankt Katharinen Hospital, Teaching Hospital of the Goethe University, Seckbacher Landstraße 65, 60389, Frankfurt am Main, Germany. 3. Institute of Neuroradiology, Goethe University, Schleusenweg 2-16, 60528, Frankfurt am Main, Germany.