1. Department of Ultrasound, West China Hospital Sichuan University, No.37 Guo Xue Xiang, Wu Hou District, Chengdu 610041, P.R. China
2. Research Institute of Pathology, West China Hospital Sichuan University, No.88 Ke Yuan South Road, Wu Hou District, Chengdu 610041, P.R. China