Department of Radiology, Seoul National University Hospital, Seoul 03080, Korea. Department of Radiology, Ajou University School of Medicine, Suwon 16499, Korea. Department of Radiology, Chungbuk National University Hospital, Cheongju 28644, Korea. Department of Radiology, Yonsei University Wonju College of Medicine, Wonju Severance Christian Hospital, Wonju 26426, Korea. Department of Radiology, Ewha Womans University Mokdong Hospital, Seoul 07985, Korea. Department of Radiology, Gachon University Gil Medical Center, Incheon 21565, Korea. Department of Radiology, Hanyang University Seoul Hospital, Seoul 04763, Korea. Department of Radiology, Korea University Anam Hospital, Seoul 02841, Korea. Department of Radiology, Korea University Guro Hospital, Seoul 08308, Korea. Department of Radiology, Soonchunhyang University Bucheon Hospital, Bucheon 14584, Korea. Department of Radiology, Hallym University Sacred Heart Hospital, Anyang 14068, Korea. Department of Radiology, Chonbuk National University Medical School and Hospital, Institute of Medical Science, Research Institute of Clinical Medicine and Biomedical Research Institute, Jeonju 54907, Korea. Department of Radiology, Severance Hospital, Yonsei University Health System, Seoul 03722, Korea. Department of Radiology, Seoul National University Bundang Hospital, Seongnam 13620, Korea.