1. From the Department of Radiology, The First Affiliated Hospital, Sun Yat-Sen University, 58 Zhongshan Rd 2, Guangzhou 510080, PR China (Q.C., L.K., Y.H., Y.L., Z.W., M.L., Y.G., H.W.); and Department of Radiology, The Eastern Hospital of the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, PR China (J.L.).