目的 探讨MRI在诊断胎盘植入 方面的应用。方法 本文回顾性分析了 2014年01月至2014年12月间20例可疑胎 盘植入的孕妇经手术证实胎盘植入的有 关资料，对MRI表现进行评估，并进行统 计学方面的分析。结果 子宫胎盘界面 的变薄或局灶性缺陷12例(P=0.002)，子 宫胎盘界面内层中断13例(P=0.012)， 正常梨形子宫消失11例(P=0.007)，胎 盘内条状低信号7例(P=0.016)，胎盘内 血管增多6例(P=0.260)，胎盘梗塞1例 (P=0.452)，胎盘的信号不均质性10例 (P=0.640)。分析显示：子宫胎盘界面的 变薄或局灶性缺陷、子宫胎盘内膜面的 中断、子宫梨形消失在区别正常和PIA 时是具有诊断价值的MRI征象。MRI诊断 PIA的整体敏感性和特异性分别是84%和 84%。其中子宫胎盘界面变薄或局灶性缺 陷在诊断PIA中是最有价值的MR表现(准 确性85%)。结论 对于诊断PIA，MRI表现 有84%的敏感性和84%的特异性。子宫胎 盘界面变薄或局灶性缺损是正常和PIA间 最具有诊断价值的MR征象。

Objective To explore the application of MRI in diagnosing the placenta implantation. Methods To evaluate the performance of MRI and make a statistical analysis, the MRI images of 20 patients with placenta implantation confirmed by operation from January 2014 to December 2014 were retrospectively analyzed. Results MRI showed 12 cases with uteroplacental interface thinning or focal defect (P=0.002), 13 cases with the interruption of uteroplacental interface inner layer (P=0.012),11 cases with the disappearance of normal pear-shaped uterus (P=0.007),7 cases within traplacental low signal bands(P=0.016),6 cases with increased subplacental vascularity (P=0.260),1 case with placental infarction (P=0.452), 10 cases within homogeneous placenta signal intensity (P=0.640).The MRI features of placenta implantation with diagnostic value were uteroplacental interface thinning or focal defect, interruption of uteroplacental interface inner layer and disappearance of normal pear-shaped uterus. The overall sensitivity and specificity of MRI in diagnosing PIA were84% and 84%, respectively. The uteroplacental interface thinning or focal defect were the most valuable MR performance in diagnosing PIA (the accuracy was85%). Conclusion The overall sensitivity and specificity of MRI in diagnosing PIA were84% and 84%, respectively. The uteroplacental interface thinning or focal defect were the most valuable MR performance in diagnosing PIA.