MRI诊断前置血管的价值

The Value of MRI in the Diagnosis of Vasa Previa

目的探讨MRI在产前诊断前置血管(VP)的临床价值。方法回顾性分析20例VP的产前MRI表现。结果产前MRI诊断VP的准确率为100%。中央性前置胎盘、边缘性前置胎盘、球拍状胎盘、帆状胎盘并发VP概率最高,分别为1.1%、1.1%、1.47%、1.47%,脐带汇入位置异常并发VP概率高于胎盘位置异常(0.22%、0.13%)。VP在不同切面上,T_2WI FSE及SSFSE序列均表现为管状或类圆形断面流空信号。20例中8例在胎盘边缘走行,14例轴位走行方向自后向前,16例冠状面和矢状面图像走行方向自下斜向上。结论 MRI多方位成像可以清晰显示VP,有较高的诊断价值。

Objective To assess the value of MRI in the prenatal diagnosis of vasa previa. Methods Prenatal MRI findings of 20 patients with vasa previa were retrospectively analyzed. Results The accuracy rate of prenatal MRI in the diagnosis of vasa previa was 100%. Complete placenta previa,marginal placenta previa,battledore placenta and velamentous cord insertion showed higher incidence rate of vasa previa（ 1. 1%,1. 1%,1. 47%,1. 47%,respectively）. The incidence of abnormal placental umbilical cord insertion site（ 0. 22%） accompanied with vasa previa was higher than that of abnormal placental location（ 0. 13%）. On both T_2WI/FSE and SSFSE sequences,vasa previa demonstrated tubular or round-like flow voids in different sections. Among the 20 cases of vasa previa,8 cases stretched the edge of the placenta,14 cases extended from back to front on axial images,16 cases extended obliquely upwards on coronal and sagittal images.Conclusion Multi-planar MRI can clearly show the vasa previa with high diagnostic value.