Value Of Three-dimensional Power Doppler Ultrasound In The Diagnosis Of Postpartum Placental Accrete

Objective:1.To detect the characteristics of three-dimensional power Doppler ultrasound images of postpartum placenta accreta.2.To evaluate the clinical value of three-dimensional power Doppler ultrasound in the diagnosis of postpartum placenta accreta,and provide imaging evidence for the clinical use of reasonable treatment plans.Methods:From January 2016 to January 2021,49 patients with suspected postpartum placenta accreta were admitted to our hospital,of whom the location,range,boundary and blood flow characteristics of the lesion were observed,compared with the pathological results in the diagnostic efficiency on postpartum placenta accreta and analyze the image characteristics of the two-dimensional and three-dimensional ultrasound.Results:1.35 patients with placenta accreta were confirmed by ultrasound examination and pathology after treatment,all of whom met the pathological diagnostic criteria.Postpartum placenta accreta accounted for 0.2%(35/15283)of pregnant women during the same period.2.Postpartum placental accreta two-dimensional power Doppler ultrasound sonogram performance: intrauterine mass hyperechoic placenta,82.9%(29/35)residual placenta,88.6%(31/35)disappearance of the posterior placenta space,the thickness from the serosal layer behind the placenta is less than 5mm 91.4%(32/35),the blood flow in the posterior placental space-uterine serosal surface is 82.9%(29/35),and the blood flow spectrum around the low-resistance trophoblast can be recorded.3.Postpartum placenta accreta three-dimensional power Doppler ultrasound sonogram performance: the blood vessels in the placenta are scattered and distributed in88.6%(29/35);the posterior placental space-uterine serosal surface blood flow is abundant in 91.4%(32/35),the blood vessels behind the placenta and the blood vessels of the uterine wall showed an interlaced distribution of 94.2%(33/35).4.Compared with the characteristics of residual placenta ultrasound,the two-dimensional ultrasound of placenta accreta is mainly demonstrated in the thinning of the myometrium and the disappearance of the boundary between the placenta and the myometrium,there is significant statistical difference.(P<0.05);three-dimensional power Doppler ultrasound manifestations are mainly scattered in the formation of blood vessels in the placenta and excessive formation of blood vessels between the posterior space vessels and the muscle wall,and the difference is statistically significant(P<0.05).5.Two-dimensional power Doppler ultrasound diagnosed 27 cases of postpartum placenta accreta,4 cases of misdiagnosis,and 8 cases of missed diagnosis.The sensitivity,specificity,positive predictive value,negative predictive value,total coincidence rate,and Youden index were 77.1%,71.4%,87.1%,55.6%,75.5%,48.5%,respectively.Three-dimensional power Doppler ultrasound diagnosed 32 cases of postpartum placenta accreta,1 case of misdiagnosis,and 3 cases of missed diagnosis.The sensitivity,specificity,positive predictive value,negative predictive value,total coincidence rate,and Youden index were 91.4%,92.8%,97.0%,81.3%,91.8%,and 84.5%,respectively.There was no statistically significant difference between the two diagnostic methods(P≥0.05).Conclusions:1.Whether or not the boundary between placenta and myometrium is clear is of diagnostic value in the diagnosis of postpartum placenta accreta by two-dimensional power Doppler ultrasound.2.The interlaced distribution of blood vessels in the posterior placenta space and the serosal surface of the uterus may be a specific sonogram of three-dimensional power Doppler ultrasound in the diagnosis of postpartum placenta accreta.3.There is no significant difference between three-dimensional power Doppler ultrasound and two-dimensional power Doppler ultrasound in the diagnosis of postpartum placenta accreta,but three-dimensional power Doppler ultrasound can stereoscopically display abnormal blood perfusion between the placenta and myometrium,and has more advantages over two-dimensional power Doppler ultrasound in sensitivity and specificity in the diagnosis of postpartum placenta accreta,as well as certain reference significance for preventing adverse obstetric outcomes.