1. From the Departments of Neurology (K.J.B., A.J.K., P.T., D.K.Z., A.V.S., J.M.G.), Radiology (D.S.), and Biostatistics (K.C.C.), University of Washington School of Medicine, Harborview Medical Center, Seattle, WA; and the University of Washington Medical Center (J.H., K.T.C.), Seattle, WA.