1. School of Computer Science and Engineering, Northeastern University, Shenyang, China
2. Key Laboratory of Intelligent Computing in Medical Image, Ministry of Education, Northeastern University, Shenyang, China
3. Department of Radiology, General Hospital of North Theater Command, Shenyang, China
4. Blizard Institute, Barts & The London School of Medicine & Dentistry, Queen Mary University of London, London, U.K.