1. From the Departments of Radiology (Y.N., F.N., N.K., M.M.) and Frontier Science for Imaging (F.H.), Gifu University, 1-1 Yanagido, Gifu 501-1194, Japan; Department of Radiology Services (R.S., T.M.) and Innovative and Clinical Research Promotion Center (T.I.), Gifu University Hospital, Gifu, Japan; and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, Mass (A.R.K.).