1. From the Departments of Neurology (M.J.L., S.J.K., S.R., G.-M.K., C.-S.C., K.H.L., O.Y.B.) and Radiology (J.C.), Samsung Medical Center, School of Medicine (M.J.L., S.J.K., S.R., G.-M.K., C.-S.C., K.H.L., O.Y.B., J.C.) and Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology (J.P.S., O.Y.B.), Sungkyunkwan University, Seoul, Korea; and Biostatistics Team, Samsung Biomedical Research Institute, Seoul, Korea (S.-Y.W.).