超声鉴别诊断瘢痕妊娠与宫腔下段非瘢痕妊娠

目的 观察二维及三维超声诊断剖宫产瘢痕妊娠（CSP）与宫腔下段非瘢痕妊娠的价值。方法 收集67例CSP患者（CSP组）和29例宫腔下段非瘢痕妊娠患者（宫腔下段非瘢痕妊娠组），以二维及三维超声观察孕囊种植部位、与剖宫产瘢痕关系和滋养血流主要来源部位，并测量剖宫产瘢痕处残余肌层厚度；建立Logistic回归模型，以ROC曲线评价其诊断效能。结果 CSP组与宫腔下段非瘢痕组间孕囊与瘢痕关系、滋养血流来源部位及瘢痕处残余肌层厚度差异均有统计学意义（P均<0.001）。Logistic回归模型显示ROC曲线下面积为0.878（P<0.001）。以预测概率=0.680为临界值，该模型预测CSP的准确率为86.46%，敏感度为89.55%，特异度为79.31%。以孕囊植入瘢痕和滋养血流来源于子宫前壁下段为诊断CSP的标准，二维与三维超声诊断CSP和宫腔下段非瘢痕妊娠的Kappa值分别为0.699和0.711。结论 通过Logistic回归模型综合分析孕囊与瘢痕关系、滋养血流来源部位和瘢痕处残余肌层厚度，可提高对CSP与宫腔下段非瘢痕妊娠的鉴别效能。

Ultrasonic differential diagnosis of scar pregnancy and lower uterine cavity non-scar pregnancy

Objective To investigate the value of two-dimensional and three-dimensional ultrasonography in differential diagnosing cesarean scar pregnancy (CSP) and lower uterine cavity non-scar pregnancy. Methods Totally 67 patients with CSP (CSP group)and 29 patients with lower uterine cavity non-scar pregnancy (lower uterine cavity non-scar pregnancy group) were enrolled. Two-dimensional and three-dimensional ultrasonography were performed to observe the gestational sac implantation site, the relationship between gestational sac and cesarean section scar and the main source of blood flow, and the residual muscle thickness of cesarean section scar was measured as well. Logistic regression model was established, and the diagnostic efficacy was evaluated with ROC curve. Results Statistical differences of relationship between gestational sac and scar, the main source of blood flow and residual muscle thickness were found between CSP group and lower uterine cavity non-scar pregnancy group (all P<0.001). The area under the ROC curve of the Logistic regression model was 0.878 (P<0.001). Taking prediction accuracy of 0.680 as a cut-off value, the accuracy of this model in predicting was 86.46%, the sensitivity was 89.55% and the specificity was 79.31%. Taking gestational sac implanted scars and nourish the blood flow from the lower anterior wall of the uterus as the diagnostic criteria for CSP, the Kappa value of two-dimensional and three-dimensional ultrasonography in diagnosis CSP and non-scar pregnancy was 0.699 and 0.711, respectively. Conclusion Comprehensive analysis of the relationship between gestational sac and scars, the main source of blood flow and residual muscle thickness with Logistic regression model can improve differential diagnostic efficacy of CSP with lower uterine cavity non-scar pregnancy.