1. From the Department of Diagnostic Radiology, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan (T.H., Y.N., F.T., Y.K, M.A., Y.B., M.I., K.A.); and Department of Clinical Radiology, Hiroshima University Hospital, Hiroshima, Japan (Y.A.).