1. Department of Neurology, School of Medicine, Kyungpook National University, Kyungpook National University Chilgok Hospital, Daegu, Korea.
2. Department of Neurology, Pusan National University Hospital, Busan, Korea.
3. Department of Neurology, Pusan National University Yangsan Hospital, Yangsan, Korea.
4. Department of Neurology, Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.