1. Department of Radiology, Pusan National University Hospital, Busan, Korea.
2. Department of Radiology and Research Institute of Radiological Science, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
3. Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
4. Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.