1. Department of Radiology, Seoul National University Hospital, Seoul, Korea.
2. Department of Radiology, Chungbuk National University Hospital, Chungbuk, Korea.
3. Human Medical Imaging & Intervention Center, Seoul, Korea.
4. Healthcare System Gangnam Center, Seoul National University Hospital, Seoul, Korea.
5. Department of Pathology, Seoul National University Hospital, Seoul, Korea.
6. Department of Preventive Medicine, Graduate School of Public Health, Seoul National University Hospital, Seoul, Korea.
7. Department of Radiology, Korea University Guro Hospital, Seoul, Korea.
8. Department of Radiology, SNU Boramae Medical Center, Seoul, Korea.