1. From the Department of Neuroradiology, Heidelberg University Hospital, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany (M.K., D.S., T.G., S.H., M.B., P.B.); Neurologie Neuer Wall, Hamburg, Germany (K.C.K.); Department of Radiology, German Cancer Research Center, Heidelberg, Germany (P.B.); and dia.log, Altoetting Center for Radiology, Altoetting, Germany (P.B.).