Objective: The present study analyzed the fetal$-$placental hemodynamic parameters in women with severe preeclampsia in second- and third-trimester pregnancy with a view to developing effective predictive indicators for preeclampsia and providing support for the prenatal clinical treatment of preeclampsia. Materials and Methods: From January 2015 to January 2019, 160 pregnant women diagnosed with severe preeclampsia at Xiangyang First People’s Hospital were recruited as the study group. The diagnostic criteria for preeclampsia were in accordance with the guidelines of the International Society for the Study of Hypertension in Pregnancy (ISSHP). A sample of 160 healthy pregnant women with normal blood pressure were selected as the control group. The GE Voluson E8 and E10 four-dimensional (4D) ultrasonic diagnostic instruments and the three-dimensional (3D) power Doppler in angio-quantitative mode were used to measure the hemodynamic parameters of the placenta, left uterine artery (LUA), right uterine artery (RUA), middle cerebral artery (MCA), umbilical artery (UA), and ductus venosus (DV) in the two groups. The above parameters were analyzed statistically using SPSS 22.0. Results: The systolic/diastolic velocity ratio (S/D), pulsatility index (PI), and resistance index (RI) of the MCA in the study group were lower than those of normal subjects of the same gestational age ($P<0.05$). These parameters in the UA were higher in the study group than those in normal subjects ($P<0.05$). The ratios between the peak ventricular systolic velocity and the peak atrial systolic velocity (S/A), pulsatility index for the vein (PIV), pre-load index (PLI), and peak velocity index for the vein (PVIV) in the DV were significantly different between the study and normal groups ($P<0.05$). The placental vascularization index (VI), flow index (FI), and vascularization flow index (VFI) were lower in the study group than those in normal subjects of the same gestational age ($P<0.05$). There were good correlations between VI, VFI and RUA, PI, with correlation coefficients of $-$0.697 and $-$0.702, respectively. FI was the indicator that had the highest diagnostic efficacy for severe preeclampsia. The predictive sensitivity of the FI with a cut-off value of 34.92 was 96.3%, and the corresponding specificity was 86.9%. Conclusions: Placental FI had the highest predictive efficacy for severe preeclampsia and provides a reliable quantitative indicator and data support for preeclampsia management. 3D power quantitative Doppler ultrasound provides a novel avenue for the study of severe preeclampsia.

目的：本研究分析了胎儿$-$妊娠中期和妊娠晚期严重子痫前期妇女的胎盘血流动力学参数，以期开发子痫前期的有效预测指标，并为子痫前期的产前临床治疗提供支持。材料和方法：从2015年1月至2019年1月，招募了160名在襄阳市第一人民医院被诊断为先兆子痫的孕妇作为研究组。子痫前期的诊断标准符合国际妊娠高血压研究协会（ISSHP）的指南。选择160例血压正常的健康孕妇作为对照组。使用GE Voluson E8和E10二维（4D）超声诊断仪和三维（3D）功率多普勒血管定量模式测量胎盘，左子宫动脉（LUA），右子宫的血液动力学参数两组分别是动脉（RUA），大脑中动脉（MCA），脐动脉（UA）和静脉导管（DV）。使用SPSS 22.0对上述参数进行统计分析。结果：研究组MCA的收缩/舒张速度比（S / D），搏动指数（PI）和抵抗指数（RI）均低于相同胎龄的正常受试者（$P<0。05$）。研究组中UA中的这些参数高于正常受试者中的这些参数（$P<0。05$）。DV中心室收缩峰值速度与心房收缩峰值速度（S / A），静脉搏动指数（PIV），预负荷指数（PLI）和静脉峰值速度指数（PVIV）之间的比率研究组和正常组之间存在显着差异（$P<0。05$）。研究组的胎盘血管化指数（VI），血流指数（FI）和血管化血流指数（VFI）均低于相同胎龄的正常受试者（$P<0。05$）。VI，VFI与RUA，PI之间具有良好的相关性，相关系数为$-$0.697和 $-$分别为0.702 FI是对严重先兆子痫具有最高诊断功效的指标。截止值为34.92的FI的预测敏感性为96.3％，相应的特异性为86.9％。结论：胎盘FI对严重先兆子痫具有最高的预测功效，并为先兆子痫的治疗提供可靠的定量指标和数据支持。3D功率定量多普勒超声为严重先兆子痫的研究提供了一条新途径。