1. Department of Radiology, Chonnam National University Medical School, Chonnam National University Hospital, Gwangju, Korea.
2. Department of Radiology, Chonnam National University Medical School, Chonnam National University Hwasun Hospital, Hwasun, Korea.
3. Department of Radiology, Soonchunhyang University Seoul Hospital, Seoul, Korea.
4. Department of Radiology, Seoul National University Hospital, Seoul National College of Medicine, Seoul, Korea.
5. Department of Radiology and Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.
6. Department of Radiology, Chungbuk National University College of Medicine, Chungbuk National University Hospital, Cheongju, Korea.