1. From the Neurology Service (P.M., C.O., M.Ru., M.Re., G.N.), Service of Diagnostic and Interventional Radiology (P.M., R.M.), Division of Clinical Pharmacology (A.M.), Institute of Social and Preventive Medicine (M.F.), and Service of Neuropsychology and Rehabilitation (A.C.), Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland; Department of Radiology, Division of Neuroradiology (M.W.), University of Virginia, Charlottesville, Va.