Shear Wave Elastography Is A Preliminary Study Of Placental Elasticity In Preeclampsia

Part1:Influencing Factors of The Placental Elastic Modulus of The Normal Second and Third Trimester Pregnancy ObjectiveTo explore the influencing factors of Shear Wave Elastrography(SWE)technology in evaluating placental elastic modulus of normal second and third trimester pregnancy.MethodsFrom January 2018 to June 2018,69 cases of pregnant women in the second and third trimester of pregnancy at the Affiliated Suzhou Hospital of Nanjing Medical University were enrolled in the study.The hemodynamic parameters of umbilical artery & bilateral uterine arteries were measured.Then,the placental elastic modulus of the central-fetal surface,central-maternal surface,peripheral-fetal surface and peripheral-maternal surface were measured by SWE technology.The correlation between placental elastic modulus and sampling areas,gestational weeks,the hemodynamic parameters were analysed.ResultsThe central-fetal surface,the central-maternal surface,the peripheral-fetal surface and the peripheral-maternal surface of normal placental elastic modulus of the second and third trimester pregnancy were 5.85±1.68 KPa,6.20±1.29 KPa,5.88±1.30 Kpa and6.24±1.23 KPa respectively.There was no significant difference in elastic modulus of different areas of the placenta(P>0.05).The second trimester and third trimester of placental elastic modulus were 5.79 ±0.67 KPa,6.17 ±0.88 KPa respectively.There was no significance difference in elastic modulus between the second and third trimester.Moreover,there was no obvious correlation between placental elasticmodulus and hemodynamic parameters of umbilical artery & bilateral uterine arteries(P>0.05).ConclusionsThe normal placental elastic modulus of the second and third trimester is not significantly correlated with the sampling area,the gestational weeks,and hemodynamic parameters of umbilical artery & bilateral uterine arteries.SWE technology can obtain the biomechanical information of placental tissue to evaluate placental function,which may become a new method for clinical evaluation of placenta.Part2:Preliminary Study of Shear Wave Elastrography in Assessing Placental Elasticity in Preeclampsia ObjectiveTo explore the clinical value of Shear Wave Elastrography(SWE)in quantitatively assessing placental elasticity in preeclampsia(PE).MethodsFrom January 2018 to June 2018,76 cases of pregnant women in the second and third trimester of pregnancy at the Affiliated Suzhou Hospital of Nanjing Medical University were enrolled,from which,22 preeclampsia petients were selected as PE group and 54 normal pregnant women were selected as the control group.The hemodynamic parameters of umbilical artery & bilateral uterine arteries were measured.Then,the placental elastic modulus of the central-fetal surface,central-maternal surface,peripheral-fetal surface and peripheral-maternal surface were measured by SWE technology.Then,the Receiver Operating Characteristic Curve(ROC)was drawn according to the mean value of elastic modulus in the four regions of placenta to obtain the optimal threshold for the diagnosis of PE,furthermore,its Sensitivity(Se),Specificity(Sp),Positive Predictive Value(PPV)and Negative Predictive Value(NPV)were calculated.ResultsThe elastic modulus of the central-fetal surface,the central-maternal surface,the peripheral-fetal surface and the peripheral-maternal surface in PE group and control group were 8.54±3.74 KPa,9.46±3.64 KPa,8.48±2.66 KPa,9.25±3.00 KPa and6.38±1.87 KPa,6.51±1.52 KPa,6.37±1.55 KPa,6.48±1.58 KPa respectively.In both of the two groups,there were no significant differences in elastic modulus of four regions of the placentas(P>0.05).The elastic modulus of PE group were significantly higher than control group(P < 0.05).The AUC(Area Under Curve)for predicting PEby the mean value of placental elastic modulus was 0.754 and the optimum threshold was 8.19 KPa.The Se,Sp,PPV and NPV were 64%,96%,88% and 87% respectively,and the coincidence rate was 87%.Moreover,placental elastic modulus was low correlated with hemodynamics parameters of uterine arteries(P < 0.05),but unrelated with that of umbilical artery(P > 0.05).ConclusionsThe placental elasticity of PE patients was significantly higher than the normal obtained by SWE technology.SWE technology may be used to predict and evaluate PE,which provides a new perspective for the clinical management of PE.