超声在妊娠早期筛查剖宫产后胎盘植入中的应用

Ultrasonography in Screening Placental Accrete with Cesarean Section in Early Pregnancy

目的评价产前超声在妊娠早期诊断胎盘植入高危孕妇(具有剖宫产史合并胎盘低置)是否存在胎盘植入的可行性。资料与方法筛选有剖宫产史、胎儿头臀径45~84 mm且合并胎盘低置的904例孕妇。所有患者的胎盘均经手术证实或随访其胎盘情况;分析确诊为胎盘植入患者早孕期胎盘的超声声像图特点,计算早孕期筛查胎盘植入的敏感度和特异度。结果产后证实胎盘植入42例(4.65%)。早孕期超声诊断胎盘植入40例,未诊断胎盘植入864例,其中超声误诊6例、漏诊8例胎盘植入。超声检查诊断胎盘植入的敏感度和特异度分别为80.95%和99.30%;胎盘植入超声征象发生率由高到低依次为胎盘内漩涡形成(64.70%)、胎盘后方彩色多普勒血流增多(55.88%)、胎盘后间隙消失(44.12%)及子宫下段前壁肌层菲薄与胎盘分界不清(35.29%)。早孕期超声诊断为胎盘植入,且产后证实为胎盘植入的34例患者中,均出现1种和(或)以上胎盘植入的超声征象;早孕期超声未发现胎盘植入的856例患者中,仅8例出现1种上述征象。与前置胎盘并植入患者比较,前置胎盘无植入以及无前置胎盘无植入患者在胎盘漩涡、胎盘后间隙消失、子宫下段前壁肌层薄而不清、胎盘后方彩色血流增多等超声征象的出现率均显著降低,差异有统计学意义(P<0.05)。结论产前超声可在妊娠早期有效诊断胎盘植入高危孕妇是否存在胎盘植入,为临床早期干预提供依据。

Purpose To evaluate the feasibility of prenatal ultrasound in the diagnosis of placental increta in high-risk pregnant women(with a history of cesarean section combined with low placenta)in early pregnancy.Materials and Methods A total of 904 pregnant women with a history of cesarean section,fetal crown-rump length between 45 mm and 84 mm combined with low placenta were enrolled in this study.All the placenta of patients were confirmed by surgery or follow-up.The characteristics of ultrasound imaging of the placenta in patients with placenta implantation in early pregnancy were analyzed,and the sensitivity and specificity of placenta implantation in early pregnancy screening were calculated.Results Forty-two cases(4.65%)of placenta implantation were confirmed by postpartum.In early pregnancy,40 cases of placenta implantation were diagnosed by ultrasound,and 864 cases were not diagnosed.Six cases were misdiagnosed by ultrasound,and eight cases were missed diagnosis.The sensitivity and specificity of ultrasound in the diagnosis of placenta implantation were 80.95%and 99.30%,respectively.The incidence of placenta implantation ultrasound signs from high to low was vortex formation in the placenta(64.70%),enhance of color Doppler signals behind the placenta(55.88%),disappearance of the posterior placenta space(44.12%),a very thin myometrium of the anterior wall of the lower uterine segment and which has unclear boundary with the placenta(35.29%).Of the 34 patients diagnosed with placenta implantation by ultrasound during the first trimester and confirmed postpartum implantation after birth,there were one or more ultrasound signs of placenta implantation.Among 856 patients with placenta implantation not detected by ultrasound during the first trimester,only eight cases showed one of the above signs.Compared with placenta previa implantation,patients without placenta previa implantation and without placenta previa implantation had placental vortex,disappearance of the posterior placental gap,thin and unclear myometrium of anterior wall of lower uterus,and colored blood flow behind the placenta,the incidence of ultrasound signs such as increase was significantly reduced(P<0.05).Conclusion Prenatal ultrasound can effectively diagnose the presence of placenta increta in the high-risk pregnant women with placenta implants in early pregnancy and provide a basis for early clinical intervention.