1. Institute of Ultrasound Imaging
2. Second Affiliated Hospital of Chongqing Medical University
3. Chongqing
4. 400010 PR China
5. Department of Ultrasound & Department of Biomedical Engineering
6. Shanghai Jiao Tong University Affiliated Sixth People's Hospital
7. Shanghai
8. 200233 PR China
9. General Hospital of Ningxia Medical University
10. 750004 PR China