From the Departments of Neurology (M.B.G., M.M., B.M.S., T.R.M., L.C., M.A., U.F., D.J.S., W.J.Z.G.) and Neurosurgery (D.B., W.J.Z.G.), and the University Institute for Diagnostic and Interventional Neuroradiology (W.V., P.R., A.H., J.K., R.W.), Inselspital Bern University Hospital and University of Bern; Graduate School for Health Sciences (M.B.G., B.M.S.) and CTU Bern (M.B.), University of Bern, Switzerland; Stroke Research Centre (M.B.G., W.Z., H.O., M.L., Y.D., D.J.W.), University College London Queen Square Institute of Neurology, United Kingdom; Service of Neurology (D.S.), Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne; Department of Radiology (T.F.), Cantonal Hospital St. Gallen; Department of Internal Medicine (F.M.), Stroke Unit and Division of Neurology, HFR Fribourg-Cantonal Hospital; Stroke Center Hirslanden (N.P.), Klinik Hirslanden Zurich; Stroke Research Group (E.C.), Department of Clinical Neurosciences, University Hospital and Faculty of Medicine, Geneva; Department of Radiology and Medical Informatics (K.-O.L.), University of Geneva; Department of Radiology and Nuclear Medicine (G.M.K.), Luzerner Kantonsspital; Stroke Center EOC (C.W.C.), Neurocenter of Southern Switzerland; Stroke Unit (J.N.), GHOL, Hôpital de zone de Nyon; Stadtspitäler Triemli und Waid (M.-L.M.), Zurich; Department of Neurology (A.M., S.W.), University Hospital and University of Zurich; Department of Radiology and Nuclear Medicine (S.S.), Kantonsspital Winterthur; Department of Neurology and Stroke Center (A.A.P., V.A., M.K., U.F., L.H.B.) and Center for Rehabilitation Rheinfelden (L.H.B.), University Hospital Basel and University of Basel; Diagnostic and Interventional Neuroradiology (M.P.), Department of Radiology and Nuclear Medicine, University Hospital Basel; Department of Neurology (R.S.), Kantonsspital Graubünden, Chur; Department of Radiology/Neuroradiology (C.N.), Kantonsspital Graubünden, Chur; Department of Neurology (M.S.), and Department of Radiology (C.B.T.), Buergerspital Solothurn; Division of Neurology (S.R.), Pourtalès Hospital, Neuchâtel; Department of Radiology (K.M.K.), Réseau Hospitalier Neuchâtelois, Switzerland; Comprehensive Stroke Service (R.J.S., D.J.W.) and Neuroradiological Academic Unit (H.R.J.), Department of Brain Repair & Rehabilitation, University College London Hospital, United Kingdom; and New Zealand Brain Research Institute (D.W.), Christchurch.