1. Department of Radiology, Dongguk University Ilsan Hospital, Goyang-shi;
2. Department of Radiology, Kwandong University, College of Medicine, Myongji Hospital, Goyang-shi;
3. Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul;
4. Department of Diagnostic Radiology, Soonchunhyang University Bucheon Hospital, Bucheon, South Korea