1. Department of Radiology, Ewha Womans University Mokdong Hospital, College of Medicine, Ewha Womans University, Seoul 07985, Republic of Korea
2. Department of Radiology, Chung-Ang University Gwangmyeong Hospital, Gwangmyeong 14353, Republic of Korea
3. Department of Radiology, Research Institute of Radiological Science, Yongin Severance Hospital, Yonsei University College of Medicine, Yongin 03186, Republic of Korea