1. From the Department of Radiology, Beijing Jishuitan Hospital, 31 Xinjiekou East Street, Beijing 100035, China (Z.G., K.L., W.L., W.Z., Y.Z., L.X., L.W., X.C.); School of Biomedical Engineering & Imaging Sciences, King's College London, St Thomas' Hospital, London, England (G.M.B.); Mindways Software Inc, Austin, Tex (J.K.B.); and Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wis (P.J.P.).