1. From the Department of Medical Ultrasonics, Institute of Diagnostic and Interventional Ultrasound (D.Y., B.Z., Y.W., M.X., M.L., W.W., Guangliang Huang, Xiaoyan Xie, Xiaohua Xie) and Organ Transplant Center (Gang Huang, C.W.), The First Affiliated Hospital of Sun Yat-Sen University, No. 58 Zhongshan Rd 2, Guangzhou 510080, People’s Republic of China.