1. Department of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul, Korea.
2. Department of Radiology, Soonchunhyang University Hospital, Soonchunhyang University College of Medicine, Seoul, Korea.
3. Department of Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, Severance Hospital, Seoul, Korea.
4. Department of Surgery, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul, Korea.