1. Department of Radiology, Taean-gun Health Center and County Hospital, Taean-eup, Taean-gun, Chungcheongnam-do, Republic of Korea.
2. Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 05505, Republic of Korea.