1. From the Departments of Neurology (S.J., K.S., O.F., M.-L.M., U.F., A.W., A.G., H.P.M., M.A.) and Diagnostic and Interventional Neuroradiology (J.G., M.E.-K., C.B., G.S.), Inselspital, University Hospital Bern and University of Bern, Bern, Switzerland.