Yajie Wang1, Lin Zhang2,3, Jiahong Dong4, Huijun Chen5. 1. Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China. 2. Hepato-pancreato-biliary Center, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University, Beijing, China. 3. Department of Radiology, Southwest Hospital, Army Medical University, Chongqing, China. 4. Hepato-pancreato-biliary Center, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University, Beijing, China. dongjiahong@mail.tsinghua.edu.cn. 5. Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China. chenhj_cbir@mail.tsinghua.edu.cn.