[1
]
Department of Radiology and Research Institute of Radiology, Asan Medical Center,
University of Ulsan College of Medicine, 86, Asanbyeongwon-gil, Songpa-gu, Seoul 138-736,
Republic of Korea.
[2
]
Department of Radiology and Research Institute of Radiology, Asan Medical Center,
University of Ulsan College of Medicine, 86, Asanbyeongwon-gil, Songpa-gu, Seoul 138-736,
Republic of Korea. Electronic address: jhshin@amc.seoul.kr.
[3
]
Department of Clinical Epidemiology and Biostatistics, Asan Medical Center, University
of Ulsan College of Medicine, 86, Asanbyeongwon-gil, Songpa-gu, Seoul 138-736, Republic
of Korea.