1. Department of Neurology, Ewha Womans University School of Medicine and Ewha Medical Research Institute, Seoul, Korea.
2. Department of Medical Science, Ewha Womans University School of Medicine and Ewha Medical Research Institute, Seoul, Korea.
3. Department of Neurology, Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea.
4. Department of Neurology, Heavenly Hospital, Goyang, Korea.