1 Department of Neurology, Ansan Hospital, Korea University Medical College, 516 Gojan-1-dong, Danwon-gu, Ansan, Gyeonggi, 15355, South Korea.
2 Department of Neurology, Ansan Hospital, Korea University Medical College, 516 Gojan-1-dong, Danwon-gu, Ansan, Gyeonggi, 15355, South Korea. kwondoya@hanmail.net.