Affiliation: | 1. Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan, P.R. China;2. Department of Radiology, Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, P.R. China |