The Value Of Prenatal Placental Implantation Magnetic Resonance Imaging Diagnosis And Its Scoring System In Predicting The Degree Of Implantation

Objectives 1 To explore the application value of magnetic resonance imaging(MRI)in the diagnosis of prenatal placenta implantation(PIA).2 To explore the diagnostic value of MRI imaging technology with different sequence stepwise combination was analyzed in PIA.3 To explore the MRI score system predicts the value of PIA implantation and provides a reliable basis for clinical treatment.Methods The time limit is January 2016 to June 2019,a total of 141 patients with high suspicion of PIA who underwent ultrasound and magnetic resonance examinations at the same gestational age in our hospital were collected,and 89 patients with PIA were confirmed by surgery or pathology,including 62 cases of placenta accreta(PA),17 cases of placenta increta(PI),and 10 cases of placenta percreta(PP).1 According to different prenatal examination techniques,the patients were divided into the US group and the MRI group,and compared the difference between the two groups in the diagnostic efficiency and implantation type of prenatal PIA.2 According to the routine PIA sequence of MRI,different step-by-step combinations are carried out: Group A: HASTE+DWI group,Group B: HASTE+FSE group,Group C: HASTE+True-FISP group.Comparison of 3 groups in the diagnosis PIA implantation position gross anatomical relationship abnormal situation and the detection of placental parenchymal abnormalities.3 The clinical data of 141 patients were retrospectively analyzed,and t-test,chi-square test,and multivariate logistic regression were used to obtain high-risk factors affecting PIA.Further analysis of prenatal MRI imaging characteristics(observing whether the morphology of the lower segment of the uterus is bulging,the placenta is substantially uniform,the uterine muscle layer is complete and the placental uterine boundary is clear,etc.).Combined with clinical high-risk factors,each item is rated 0?2,and a rating scale is developed.And according to the scale,calculated the total score of each type of implant patients,compared and calculated the score among each type.Results 1 The sensitivity and accuracy of prenatal MRI in the diagnosis of PIA are higher than US,but there was no significant difference between the two groups(both P> 0.05);The Kappa values of the MRI group and US group were 0.753 and 0.804,respectively.MRI diagnostic PIA fits perfectly;the difference in the detection rate of diagnostic PI between the two groups was statistically significant(P<0.05),and the difference in the detection rate of PA and PP weren't statistically significant(P>0.05).2 There was no significant difference in the diagnosis of the general position of the placental implantation in the three groups with different sequence combinations(all P>0.05);When the general anatomical relationship of the implantation positions was displayed,there was a statistical difference between the three groups(P<0.05).There was no significant difference between group A and group B(P>0.05);there was a significant difference between group A and group C(P<0.05);The same results was shown between group B and group C(P<0.05);when the parenchymal change of the placenta is shown,the difference between the three groups is statistically significant(P<0.05),and the difference between group A and group B is not statistically significant(P>0.05);compared with group A and group C,the difference was statistically significant(P<0.05);The same results between group B and group C was statistically significant differences(P<0.05).3 The number of abortions,the number of cesarean sections,and the combination of placenta previa are risk factors for PIA.According to the developed rating scale,the average score for the adhesion type was 3.48±1.17,for the implant type was 6.41±1.37,and for the penetrating type was 8.80±1.31.The differences among the three groups were statistically significant(all P<0.05).According to the results of the ROC curve,the area under the curve was 95.1%.When the score is?4.5,the sensitivity is 94.1% and the specificity is 82.3%.Therefore,it can be considered that the cutoff value of adhesion placenta implantation and implantable placenta implantation is 5 points;when the area under the curve is 89.1% and the score is?7.5,the sensitivity is 80.0% and the specificity is 76.5%,the cutoff value of implantable placenta and penetrating placenta is 8 points.Conclusions 1 As a non-invasive examination technique,MRI has a high efficiency in diagnosing prenatal placenta implantation,and has a good consistency with intraoperative or pathological diagnosis,especially in the diagnosis of implantable placenta implantation.Guiding significance.2 HASTE+True-FISP step-by-step combined sequence observation of placental implantation has higher application value,especially in observing the changes of placental parenchymal signals and the relationship among placenta,uterus,and so on.It can provide a reliable imaging basis for the clinic.3 MRI scoring system is effective in assessing types of placenta implantation and predicting its associate risks.A score of?5 is used as a boundary to predict adhesion and implantable placenta implantation.The score is ?8 implies a higher risk of placenta percreta.Figure 4;Table 11;Reference 131.