1. Department of Radiology, Severance Hospital, Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
2. Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
3. Department of Radiology, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
4. Department of Radiology, Seoul National University Hospital, Seoul, Korea.
5. Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.
6. Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea.
7. Department of Radiology, Korea University Hospital, Korea University College of Medicine, Seoul, Korea.