1. Department of Ultrasound Medicine, The First People's Hospital of Linhai City, Linhai, Zhejiang 317000, P.R. China
2. Department of Ultrasound Medicine, and State Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital School of Medicine Zhejiang University, Hangzhou, Zhejiang 310000, P.R. China
3. Department of Ultrasound Medicine, and State Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases, Women's Hospital School of Medicine Zhejiang University, Hangzhou, Zhejiang 310000, P.R. China