Application Values Of Real-time Shear Wave Elastography Evaluated Placental Elasticity Of Pre-eclampsia In The Third Trimester Of Pregnancy

Objective:1.The real-time Shear Wave Elastography(SWE)technique was applied to measure the young's modulus of the placenta of patients with pre-eclampsia(PE)and the normal control group,to analyze the application values of SWE in evaluating the placental elasticity of PE.2.Color Doppler flow imaging(CDFI)was used to measure the related hemodynamic parameters,and the values in evaluating placental function of PE patients were discussed.Materials and methods:From October 2017 to October 2018,a total of 286 cases of pregnant women with advanced pregnancy who visited the outpatient and inpatient departments of our hospital were collected,and 55 cases were excluded to meet the requirements.Finally,171 cases of pregnant women in the normal control group and 60 cases in the PE group were included.Subcutaneous fat thickness by two-dimensional grayscale ultrasound.One of the first things to be done by CDFI was to measure the ratio of the systolic peak value of umbilical artery(UmbA),uterine artery(UteA)and middle cerebral artery(MCA)of each group(S/D value),resistance index(RI),pulsatility index(PI).The elastic modulus values at the center and edge of the placenta were measured by SWE technique--daughter respectability,middle placenta and maternal surface(mean values were measured 3 times respectively).The differences in the elastic values of placentas in each group were compared,and the differences in the hemodynamic parameters were analyzed.The correlation between the young's modulus of placentas and hemodynamic parameters was discussed.Finally,1 minute Apgar score was followed up to investigate the correlation between young's modulus of placenta and 1 minute Apgar score.To explore the value of SWE imaging in evaluating placental function in PE patients.Results:1.These differences in age,weight,subcutaneous fat thickness and BMI between the PE group and the normal control group were statistically significant,and the above indexes in the PE group were all higher than those in the normal group,while the differences in gestational weeks and height between the two groups were not statistically significant.2.There was no significant difference in young's modulus between the central placenta and the peripheral placenta between the two groups(P > 0.05);There was no significant difference in young's modulus between the normal control group and the late pregnancy group(P > 0.05).3.These difference in young's modulus of placenta between the PE group and the control group was statistically significant(P < 0.05),and the young's modulus of placenta in all parts of the PE group was greater than that of the control group.4.Measurement of young's modulus value placenta SWE technology(central)to diagnose pathological changes of PE area under the ROC curve is about 0.915,8.385 kPa is cutoff value in the diagnosis of PE,the sensitivity of 80.0% and a specific degree of 94.7%,SWE technology measure placenta young's modulus(edge)to diagnose pathological changes of PE area under the ROC curve is about 0.896,7.865 kPa for cutoff value in the diagnosis of PE,the sensitivity of 80.0%,specific degree 91.8%,SWE technology measure the average young's modulus(Emean)in the diagnosis of placenta PE diseased area under the ROC curve is about 0.908,The sensitivity and specificity of 8.245 kPa for the diagnosis of PE were 78.3% and 94.7% respectively.5.S/D value,RI value and PI value of UteA in PE group and normal control group were statistically different(P < 0.05),while UmbA,MCA and other values were not statistically different(P > 0.05).6.The average value of young's modulus of placenta in PE group was correlated with S/D value,RI value and PI value of UteA,and the correlation coefficient between young's modulus of placenta and RI of UteA was the highest.7.The area under the ROC curve of the S/D diagnosis of UteA on the left and right was 0.896 and 0.88,respectively.The area under the ROC curve of the left and right UteA RI diagnosed PE lesions was about 0.895 and 0.88,respectively.The area under the ROC curve of the PI diagnosed PE lesions of the left and right UteA was about 0.896 and 0.879,respectively.Conclusion:1.The difference of young's modulus of each placenta part was not statistically significant.The young's modulus of any placenta part could represent placental elasticity.The young's modulus of the normal control group did not change with the gestational age in the late pregnancy.2.The young's modulus value of placenta in the PE group was larger than that in the normal control group,and SWE young's modulus value had higher diagnostic efficacy in predicting PE patients.3.The S/D value,RI value and PI value of UteA in the PE group were all larger than those in the normal control group,and the S/D value,RI value and PI value of UteA predicted higher diagnostic efficacy in PE patients.4.The S/D value,RI value and PI value of UteA in the PE group were correlated with the placental young's modulus value,and the correlation between RI value and the placental young's modulus value was the highest.5.SWE technology provides a new method for clinical prediction of PE due to its advantages of non-invasive,simple,good repeatability and high diagnostic value.