1. Department of Radiology, Seoul National University Hospital, Seoul, Korea.
2. Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul, Korea.
3. Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul, Korea.
4. Department of Radiology, Seoul National University Bundang Hospital, Seoul, Korea.
5. Department of Radiology, National Cancer Center, Goyang, Korea.
6. Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Seoul, Korea.
7. Department of Radiology, Ewha Womans University Mokdong Hospital, Ewha Womans University School of Medicine, Seoul, Korea.
8. Department of Radiology, Ajou University Medical Center, Suwon, Korea.