1. Department of Radiology, Yeoido St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
2. Department of Radiology, Gangneung Asan Hospital, Ulsan University College of Medicine, Gangneung, Korea.
3. Department of Radiology, Korea University Guro Hospital, Seoul, Korea.
4. Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
5. Department of Radiology, Ajou University Hospital, Ajou University School of Medicine, Suwon, Korea.
6. Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.