1. Department of Neurology, Kyungpook National University Chilgok Hospital, School of Medicine, Kyungpook National University, Daegu, Korea.
2. Department of Neurology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
3. Department of Neurology, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon, Korea.