剪切波技术对先兆子痫患者胎盘弹性的初步研究

目的：探讨剪切波弹性成像（shear wave elastography,SWE）技术定量分析先兆子痫患者胎盘弹性的临床应用价值。方法：选取单胎妊娠妇女76例（先兆子痫组22例，健康对照组54例），常规测量脐动脉、双侧子宫动脉血流动力学参数（S/D、PI、RI），SWE测量胎盘中央胎儿面、中央母体面、边缘胎儿面、边缘母体面四个不同区域弹性模量值。根据胎盘四个区域平均弹性模量值绘制ROC曲线，获取诊断先兆子痫的最佳临界值，计算敏感性、特异性、阳性预测值、阴性预测值。结果：先兆子痫组胎盘中央胎儿面、中央母体面、边缘胎儿面、边缘母体面弹性模量值分别为：8.54±3.74KPa、9.46±3.64KPa、8.48±2.66KPa、9.25±3.00KPa，健康对照组弹性模量值分别为：6.38±1.87KPa、6.51±1.52KPa、6.37±1.55KPa、6.48±1.58KPa，先兆子痫组四个区域弹性模量值均高于健康对照组，差异有统计学意义（P＜0.05）。两组资料胎盘四个区域之间弹性模量值差异无统计学意义（P＞0.05）。胎盘弹性模量平均值预测先兆子痫的ROC曲线下面积为0.754，界值为8.19KPa，敏感性、特异性、阳性预测值、阴性预测值分别为64%、96%、88%、87%，符合率87%。胎盘弹性模量值与双侧子宫动脉血流动力学参数低度相关（P＜0.05），与脐动脉血流动力学参数无显著相关性（P＞0.05）。结论：先兆子痫孕妇胎盘硬度较正常孕妇高，SWE技术可以定量获得胎盘组织硬度，有助于评估先兆子痫孕妇胎盘功能。

Preliminary Study of Shear Wave Elastography in Placental Elasticity evalutation in Preeclampsia

Objective:To explore the clinical value of shear wave elastography(SWE) in quantitative evaluating placental elasticity with preeclampsia. Methods:The hemodynamics of umbilical artery and bilateral uterine artery (S/D, PI, RI) were measured routinely in 76 singleton pregnant women (22 preeclampsia cases in group A and 54 cases in healthy group B).The modulus of elasticity in four different regions of placenta,incuding central fetal surface,central maternal surface,marginal fetal surface and marginal maternal surface,were measured by SWE.Then,the ROC curve was drawn according to the average modulus of elasticity in the four regions of the placenta to obtain the best critical value for the diagnosis of preeclampsia then, its sensitivity, specificity, positive predictive value and negative predictive value were calculated.Results:In the group A, The modulus of elasticity of the central fetal surface, the central maternal surface, the marginal fetal surface and the marginal maternal surface in group A and group B were 8.54 ±3.74KPa, 9.46±3.64KPa, 8.48±2.66KPa and 9.25±3.00KPa and 6.38±1.87KPa, 6.51±1.52KPa, 6.37±1.55KPaand 6.48±1.58KParespectively.The modulus of elasticity of group A were higher than group B(P < 0.05). The difference in the elasticity of four regions between the two groups had no statistically difference (P > 0.05).The area under the ROC curve for predicting preeclampsia by the mean value of placental elasticity was 0.754 and the threshold value was 8.19 KPa. The sensitivity, specificity, positive predictive value and negative predictive value were 64%, 96%, 88%, 87%, respectively, and the coincidence rate was 87%. Moreover,placental elasticity was significantly correlated with hemodynamics paremeters of uterine arteries (P < 0.05), but insignificantly withthat of umbilical arteries (P > 0.05).Conclusion:The modulus of elasticity of placental in preeclampsia is higher than that of normal pregnancies.SWE can quantitatively obtain the placental tissue stiffness, which can help evaluate the placental function of pregnant women with preeclampsia