Abstract: Objective To evaluate the accuracy of three-dimensional transvaginal ultrasonography (TVS-3D) in the evaluation of intrauterine adhesions (IUA) and establish a scoring classification system for IUA. Methods A total of 112 women with suspected IUA, Who underwent TVS-3D examination and hysteroscopy were enrolled in this retrospective study from September 2019 to January 2020. Hysteroscopy was used as the gold standard, to evaluate diagnostic accuracy of TVS-3D with specificity and sensitivity, and to assess the agreement of TVS-3D and hysteroscopy in mapping extent of IUA. According to European Society of Gynecological Endoscopy ( ESGE) classification system, an independent scoring classification system based onTVS-3D coronal imaging was preliminary build up, to obtain cut-off value by area under receiver operating characteristic (ROC) curve. Results The overall sensitivity and specificity of TVS-3D were 82.6% and 65.0%, respectively, and Kappa value was 0.405 compared to hysteroscopy. The agreement of TVS-3D and hysteroscopy in mapping extent of IUA on both side walls and central upper/middle/lower segment were moderate to substantial (Kappa 0.771-0.894 and 0.500-0.610, respectively). The best cut-off value for severe adhesion with TVS-3D scoring system was 9.5 (AUC 0.929, Youden index 0.76, sensitivity 81.1%, specificity 94.9% ). Conclusion TVS-3D showed certain accuracy in the assessment of IUA, especially for the side walls and central part of the uterine cavity. The new scoring system based on three-dimensional ultrasound coronal imaging of uterine cavity has high accuracy in diagnosis of severe intrauterine adhesion and has clinical application value.

Key words: transvaginal three-dimensional ultrasound, intrauterine coronal plane, intrauterine adhesion, scoring system