Application Value Of Crystal Vue Technique In Placenta Accreta Spectrum Disorders

ObjectivePlacenta accreta spectrum disorders(PAS)is a serious complication of pregnancy.It is an important cause of postpartum hemorrhage,perinatal emergency hysterectomy,and maternal mortality.The accurate prenatal evaluation of the degree of PAS is of great significance to improve maternal delivery outcomes.At present,conventional ultrasonography can detect PAS,but it still has limitations in the classification of PAS.The main purpose of this study was to explore the accuracy and clinical value of Crystal Vue technique combined with conventional ultrasonography in the diagnosis and classification of PAS.MethodsA total of 162 pregnant women at risk of PAS were selected from the First Affiliated Hospital of Shantou University Medical College from January 2018 to March 2021.All pregnant women underwent conventional ultrasonography and Crystal Vue ultrasonography.Collect the general information and prenatal ultrasound images of all pregnant women,and track their intraoperative and postoperative conditions.According to the postoperative diagnosis as the "gold standard",pregnant women were divided into the PAS group and the non-PAS group,and the general information,surgical information of the two groups of pregnant women were compared.The kappa(k)test was used to evaluate the consistency of conventional ultrasonography and Crystal Vue technique combined with conventional ultrasonography with postoperative diagnosis.The sensitivity,specificity,positive predictive value and negative predictive value of five two-dimensional ultrasound signs in the diagnosis of PAS were calculated respectively,and the ROC curve of each two-dimensional ultrasound sign in the diagnosis of PAS was drawn.According to the prenatal ultrasound images,pregnant women were divided into the complete "tramline" group and the interrupted "tramline" group,and the need for peripartum hysterectomy,intraoperative blood loss,the need for blood transfusion and length of surgery of the two groups of pregnant women were compared.Find out the perioperative outcomes related to the "tramline" and the ROC curve of "tramline" predicts relevant perioperative outcomes was drawn.Results1.There was no statistically significant difference in age,number of pregnancies and history of intrauterine operation between PAS group and non-PAS group(P > 0.05);There were statistically significant differences in the number of deliveries,history of cesarean section,gestational age of delivery,intraoperative blood loss,need for blood transfusion,length of surgery and length of admission in the postpartum period(P < 0.05).2.The diagnostic accuracy of conventional ultrasonography was 87.65%.The diagnostic accuracy of Crystal Vue technique combined with conventional ultrasonography was 92.59%.The difference between them was statistically significant(P < 0.05).The conventional ultrasound diagnosis was substantially consistent with postoperative diagnosis(k=0.699,P <0.01).The Crystal Vue technique combined with conventional ultrasound diagnosis was perfectly consistent with the postoperative diagnosis(k=0.860,P < 0.01).3.In the diagnosis of PAS by conventional ultrasonography,the sensitivity of loss of the retroplacental clear zone,abnormal placental lacunae,thinning or disappearance of myometrium,irregular or interrupted bladder wall,and subplacental and/or uterovesical hypervascularity were 76.27%,71.19%,44.07%,10.17%,72.88%.The specificity was 93.20%,99.03%,96.17%,100.00%,94.17%.The positive predictive values were 86.54%,97.67%,86.67%,100.00%,87.76%.The negative predictive values were 87.27%,85.71%,75.00%,66.03%,85.84%.The areas under the ROC curve were 0.847,0.851,0.701,0.551,0.835(P <0.01).4.There were statistically significant differences in the need for hysterectomy,intraoperative blood loss and length of surgery between the complete "tramline" group and the interrupted "tramline" group(P < 0.05).There was no significant difference in the need for blood transfusion(P > 0.05).The area under the ROC curve of "tramline" for predicting the need for hysterectomy,intraoperative blood loss and the complexity of the surgery were 0.850,0.880,0.936(P < 0.01).Conclusion1.Compared with conventional ultrasonography,Crystal Vue technique combined with conventional ultrasonography can improve the accuracy of prenatal ultrasound diagnosis of PAS.2.Crystal Vue technique combined with conventional ultrasonography can determine the classification of PAS.3.Abnormal placental lacunae is the most effective in the diagnosis of PAS among two-dimensional ultrasonographic features.4."Tramline",the characteristic sign of Crystal Vue,is a good predictor in terms of the need for hysterectomy,intraoperative blood loss and the complexity of the surgery,which can provide a basis for the surgical plan.