1. From the Departments of Radiology and Research Institute of Radiology (S.B.H., S.S.L., J.H.K., H.J.K., J.H.B.), Pathology (S.M.H.), and Surgery (K.B.S., S.C.K.), University of Ulsan College of Medicine, Asan Medical Center, 88 Olympic-Ro 43-Gil, Songpa-Gu, Seoul 138-736, Korea.