1. Department of Radiology, Samsung Medical Center, School of Medicine Sungkyunkwan University Seoul South Korea
2. Department of Neurology, Samsung Medical Center, School of Medicine Sungkyunkwan University Seoul South Korea
3. Department of Radiology Kyung Hee University Hospital at Gangdong Seoul South Korea
4. Department of Radiology Soonchunhyang University Bucheon Hospital Bucheon South Korea