1. Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
2. Department of Radiology, Soonchunhyang University College of Medicine, Cheonan hospital, Cheonan, Republic of Korea
3. Department of Radiology, Chungnam National University Hospital, Chungnam National University of College of Medicine, Daejeon, Republic of Korea
4. Statistics and Data Center, Samsung Medical Center, Seoul, Republic of Korea