Rui-Qi Zou1, Hai-Jie Hu1, Fu-Yu Li2. 1. Department of Biliary Surgery, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan Province, China. 2. Department of Biliary Surgery, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan Province, China. lfy_74@hotmail.com.