1. Departments of Radiology, The Second Xiangya Hospital, Central South University, Changsha 410011, Hunan, P. R. China
2. Departments of Radiology, Zhuzhou Central Hospital, Zhuzhou 412000, Hunan, P. R. China
3. Institute of Clinical Pharmacy & Pharmacology, Jining First People's Hospital, Jining Medical University, Jining 272000, P. R. China
4. Department of Diagnostic Radiology Yong Loo Lin School of Medicine, National University of Singapore, 119074, Singapore