1. College of Computer Science and Technology, Zhejiang University, Hangzhou, China
2. Department of Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China
3. College of Information Science and Engineering, Ritsumeikan University, Shiga, Japan
4. Radiology Department, Tokyo Metropolitan University, Tokyo, Japan
5. Radiology Department, Shiga University of Medical Science, Shiga, Japan
6. College of Information Science and Engineering, Ritsumeikan University, Kusatsu, Japan