早期胎盘植入的MRI表现

目的 探讨早期妊娠胎盘植入的MRI表现.资料与方法 回顾性分析经手术病理证实为早期胎盘植入的18例患者的MRI表现.结果 18例中术前16例MRI诊断为胎盘植入,1例诊断为不除外胎盘植入,1例诊断未见明显异常,MRI诊断准确率为89％.MRI上16例表现为子宫不同程度增大,子宫结合带完整性破坏,肌层局部变薄或不规则破坏,T2WI低信号的子宫肌壁内出现高信号灶,11例病灶内见混杂信号影.2例仅累及子宫结合带,11例突入肌层或肌层局部明显变薄,5例基本位于肌层内.增强扫描示16例病灶呈不均匀强化、边缘强化明显,14例病灶内见结节样、花瓣样强化,7例坏死区不强化,16例增强中晚期持续明显强化.扩散加权成像(DWI)上4例病灶呈明显高信号.结论 早期妊娠胎盘植入MRI主要表现为子宫内膜及结合带不完整,肌层局部变薄或不规则破坏,T2WI低信号的子宫肌内出现高信号灶.

MRI Features of Placenta Accreta at the Early Gestational Stage

Purpose To investigate the MRI manifestations of placenta accreta at the early gestational stage.Materials and Methods MRI manifestations of 18 cases with placenta accrete at the early gestational stage and confirmed pathologically were retrospectively analyzed.Results Before operation MRI diagnosed 16 of 18 cases with placenta accrete,1 case equivocal,1 case normal.The accuracy was 89%.In 16 cases the uterus was enlarged.The integrity of junctional zone was lost.In 11 cases,the muscular layer became thin or irregular.The hyperintense placenta accreta appeared in hypointense muscular layer on T2WI with mixed signal.In 2 cases,only the junctional zone with endometria was involved.In 11 cases,the muscle was involved or thinner.Lesions were located within muscular layer in 5 cases.With contrast enhancement,16 cases were nonuniformly enhanced with periphral enhancement.In 14 cases,the enhancement was nodular or petal-like.The nocrotic area was not enhanced in 7 cases.In 16 cases the enhancement continued to be significantly in mid and late phases.4 cases showed high signal on DWI.Conclusion The MRI features of placenta accreta at the early stage are loss of endometria and cjunctional zone integrity,thinner muscular layer,and hyperintensity within hypointense muscular layer on T2WI.