1. Department of Neurosurgery, The 306th Hospital of the People's Liberation Army, Beijing 100101, P.R. China
2. Research Institute of Surgery, State Key Laboratory of Trauma, Burns and Combined Injury, Third Military Medical University, Chongqing 400042, P.R. China
3. Department of Radiology and Molecular Imaging Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
4. The Professional Laboratory, College of Materials Science and Engineering, Sichuan University, Chengdu, Sichuan 610065, P.R. China