1. From the Department of Neurology (A.R.S., S.M., A.A.R., R.D.B., D.S.K., R.C.P., J.G.-R.), Mayo Clinic Rochester, MN; Department of Neurology (A.R.S.), University of Calgary, Canada; Department of Neurology (A.C.), Boston University Chobanian & Avedisian School of Medicine; and Department of Radiology (P.V., C.R.J.), Department of Pathology (A.T.N., R.R.R.), Department of Quantitative Health Sciences (S.A.P.), and Health Sciences Research (T.G.L.), Mayo Clinic Rochester, MN.