[1] Sungkyunkwan Univ, Samsung Changwon Hosp, Sch Med, Dept Neurol, Chang Won, South Korea
[2] Seoul Natl Univ, Bundang Hosp, Cerebrovasc Ctr, Dept Neurol, Songnam, South Korea
[3] Seoul Med Ctr, Dept Neurol, Seoul, South Korea
[4] Sungkyunkwan Univ, Samsung Med Ctr, Stroke & Cerebrovasc Ctr, Sch Med,Dept Neurol, Seoul, South Korea
[5] Asan Med Ctr, Clin Res Ctr, Seoul, South Korea
[6] Korea Univ, Coll Med, Dept Biostat, Seoul 136705, South Korea
[7] Michigan State Univ, Coll Human Med & St Marys Hlth Care Mercy Hlth, Dept Translat Sci & Mol Med, Grand Rapids, MI USA