1. Department of Rehabilitation Medicine; Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea; Seoul; South Korea
2. Department of Neurology; Korea University College of Medicine; Seoul; South Korea
3. Department of Neurology; Seoul National University Bundang Hospital, Seoul National University, College of Medicine; Seoul; South Korea
4. Department of Rehabilitation Medicine; Korea University College of Medicine; 80 Guro Gu, Guro Dong; Seoul; South Korea
5. Department of Medical Sciences; Graduate School of Medicine, Korea University; Seoul; South Korea