孕期胎盘植入及其范围分级的MRI影像特征及临床价值研究

摘要

目的:探讨孕期胎盘植入的磁共振成像(M RI)影像特征及植入范围M RI分级的临床价值.方法:收集经过B超检查疑为胎盘植入患者60例,均在孕期进行M RI检查,孕妇选择仰卧位,行纵、横及动态检测,重点检查胎盘部位,患者足先进方式,选用相控阵体部表面线圈,扫描范围为趾骨联合至宫底,收集M RI检查资料,由两名影像学副主任医师采用盲法进行阅读,根据M RI检查横断面上最大覆盖面分级,观察M RI检查胎盘植入特征及评价M RI在诊断胎盘植入及分级中的临床价值.结果:M RI主要特征可以看出T2WI低信号带在胎盘植入中变化最为明显,其次为胎盘信号不均衡,胎盘植入严重程度与T2WI低信号带面积呈现明显的正相关关系(rs=0.576,P<0.05);M RI诊断结果:无胎盘植入10例,胎盘黏连15例,胎盘植入24例,胎盘穿透11例,M RI检查胎盘植入灵敏度97.9%、特异度75.0%、正确指数0.73、符合率93.3%、阳性预测值94.0%、阴性预测值90.0%;根据M RI横断面最大覆盖面分级:1级13例、2级27例、3级8例,选择常规保守治疗1级成功率100.0%,2级为25.9%,3级12.5%,差异具有统计学意义(P<0.05).结论:M RI在孕期胎盘植入诊断中具有较高的临床符合率,T2WI低信号带变化最为明显,M R分级对患者选择治疗方法具有一定参考价值.%Objective:To investigate the clinical value of magnetic resonance imaging(MRI)imaging and im-plantation of MRI in placenta previa during pregnancy.Methods:60 patients with placental implantation were en-rolled All patients underwent MRI examination during pregnancy.The pregnant women chose supine position,lon-gitudinal,transverse and dynamic detection.Check the placenta area,the patient foot advanced mode,the use of phased array surface coil,scan the scope of the phalanx to the bottom of the uterus,the collection of MRI data,by two imaging chief physician blind reading,according to MR cross-section On the maximum coverage grade,to ob-serve the placental implantation characteristics of MRI and evaluate the clinical value of MRI in the diagnosis of pla-centa implantation and grading.Results:The main features of MRI can be seen that T2WI low signal band was most obvious in placenta accreta,followed by placental signal imbalance,placental implant severity and T2WI low signal band area showed a positive correlation(rs= 0.576,P<0.05);MRI diagnosis:no placenta accreta in 10 cases, placental adhesions in 15 cases,placenta accreta in 24 cases,placenta penetrating in 11 cases,M RI examination pla-cental implant sensitivity 97.9%,specificity 75.0%,the correct index 0.73,the coincidence rate was 93.3%,the positive predictive value was 94.0% and the negative predictive value was 90.0%.According to the maximum cover-age of the MR cross-section:13 cases in grade 1,27 cases in grade 2 and 8 in grade 3,100.0%,25.9% in grade 2 and 12.5% in grade 3,the difference was statistically significant(P<0.05).Conclusion:MRI has a high clinical coincidence rate in placental implantation during pregnancy,T2WI low signal band is the most obvious change,MR grade has a certain reference value for patients to choose treatment.