1. Department of Radiology, Soonchunhyang University Hospital Bucheon, Bucheon, Korea.
2. Department of Radiology, Hanil General Hospital, Seoul, Korea.
3. Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
4. Department of Radiology, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
5. Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
6. Department of Radiology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea.
7. Department of Radiology, Seoul National University Hospital, Seoul, Korea.
8. Department of Radiology, Incheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Incheon, Korea.
9. Department of Radiology, Jeju National University Hospital, Jeju, Korea.
10. Department of Radiology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
11. Department of Radiology, Korea University Guro Hospital, Seoul, Korea.