1. Department of Radiology, Konkuk University School of Medicine, Konkuk University Medical Center, 120-1, Neungdong-ro, Hwayang-dong, Gwangjin-gu, Seoul 05030, Korea.
2. Department of Radiology, Gachon University, Gil Medical Center, Incheon, Korea.
3. Department of Neurology, Konkuk University School of Medicine, Seoul, Korea.