[1] Sungkyunkwan Univ, Sch Med, Samsung Med Ctr, Dept Neurol,Kangnam Ku, Seoul 135710, South Korea
[2] Sungkyunkwan Univ, Sch Med, Samsung Med Ctr, Dept Clin Pathol,Kangnam Ku, Seoul 135710, South Korea
[3] Sungkyunkwan Univ, Sch Med, Samsung Med Ctr, Dept Diagnost Pathol,Kangnam Ku, Seoul 135710, South Korea