胎儿生长受限的胎盘MRI表现

Magnetic Resonance Imaging of Placenta in Fetal Growth Restriction

目的探讨胎儿生长受限(FGR)的胎盘在MRI上的形态学及信号改变特征。方法回顾性分析2016年5月~2017年4月在华中科技大学同济医学院附属同济医院行MRI检查的孕妇32例,其中有超声报道胎儿FGR 14例,非FGR 18例。MRI扫描均采用半傅里叶单次激发快速自旋回波序列(HASTE),对孕妇子宫行矢、冠、轴面扫描,测量胎盘相关数值,主要包括胎盘体积、胎盘最大厚度、胎盘最大厚度/胎盘体积、胎盘/羊水信号以及胎盘病灶体积(如出血、梗死等)。结果 FGR组和非FGR组的平均胎盘最大厚度分别为50.2mm和38.8mm;平均胎盘体积分别为5.23×105 mm3和6.62×105 mm3;胎盘最大厚度/胎盘体积分别为9.60×10-5和5.86×10-5,胎盘/羊水信号为0.539和0.678;胎盘病灶体积分别为3.21×105 mm3、1.02×105 mm3。FGR的胎盘形态表现为平均胎盘体积减小(P<0.05),厚度增加(P<0.01)成球形,胎盘最大厚度/胎盘体积增加(P<0.01),胎盘/羊水信号降低(P<0.01),胎盘内病灶体积显著增加(P<0.01)。结论 FGR的胎盘MRI表现与胎盘体积、厚度、胎盘厚度/胎盘体积、胎盘/羊水信号、胎盘的病灶体积等指标有关,所以当FGR病例行MRI检查时,应常规对其胎盘状况进行评估。

Objective To evaluate morphological and signal intensity changes of fetal growth restriction(FGR)placenta on magnetic resonance imaging.Methods Totally,32 pregnant women receiving the fetal MRI in our hospital between May 2016 and April 2017 were retrospectively analyzed.There were 14 FGR cases diagnosed by ultrasound,and 18 cases of normal growth fetus.Sagittal,transverse and coronal HASTE sequences were performed.Data were collected on the placental maximum thickness,volume,ratio of placental thickness to volume,ratio of placenta to amniotic fluid signal intensity,and the placental lesion volume such as infarction and haemorrhage.Results For FGR group and normal growth fetus,the mean placental maximum thickness was 50.2 mm and 38.8 mm,the mean placental volume was 5.23×105 mm3 and 6.62×105 mm3,the ratio of placental thickness to volume was 9.60×10-5 and 5.86×10-5,the mean ratio of placenta to amniotic fluid signal intensity was 0.539 and0.678,and the placental lesion volume was 3.21×105 mm3 and 1.02×105 mm3.For FGR group,the mean placental volume was decreased(P<0.05),mean placental maximum thickness increased(P<0.01),the ratio of placental thickness to volume increased(P<0.01),the mean ratio of placenta to amniotic fluid signal intensity decreased(P<0.01),and the placental lesion volume increased(P<0.01). Conclusion FGR placenta is associated with placental maximum thickness,placental volume,ratio of placenta to amniotic fluid signal intensity and the placental lesion volume.When FGR cases receive MRI examination,assessment of the placenta should be routinely performed.