1. Department of Radiology Beijing Friendship Hospital, Capital Medical University Yongan Road 95, West District, Beijing 100050 China
2. Department of Radiology Weihai Municipal Hospital Heping Road 70, Huancui District, Weihai 264200 China
3. Department of Liver Research Center Beijing Friendship Hospital, Capital Medical University Yongan Road 95, West District, Beijing 100050 China