From the Section of Neuroradiology (M.S., B.D., C.H., S.S.).
Division of Diagnostic Imaging, Diagnostic Ultrasound Unit of the Institute of Obstetrical and Gynecological Imaging (E.H.).
AJNR Am J Neuroradiol. 2022 Apr;43(4):620-626. doi: 10.3174/ajnr.A7475. Epub 2022 Mar 24.
Single intrauterine fetal death increases the risk of antenatal brain lesions in the surviving twin. We evaluated the prevalence of structural brain lesions, biometry, and diffusivity on routine third trimester MR imaging performed following single intrauterine fetal death.
In a retrospective MR imaging-based cohort study, we compared 29 monochorionic twins complicated with single intrauterine fetal death (14 following laser ablation treatment for twin-to-twin transfusion syndrome, 8 following selective fetal reduction, and 7 spontaneous) with 2 control cohorts (49 singleton fetuses and 28 uncomplicated twin fetuses). All fetuses in the single intrauterine fetal death group underwent fetal brain MR imaging as a routine third trimester evaluation. Structural brain lesions were analyzed. Cerebral biometry and diffusivity were measured and compared.
Brain lesions consistent with the evolution of prior ischemic injury were found in 1 of 29 fetuses, not detected by ultrasound. No acute brain infarction, hemorrhage, or cortical abnormalities were found. Supratentorial biometric measurements in the single intrauterine fetal death group were significantly smaller than those in the singleton group, but not significantly different from those in the uncomplicated twin group. There were no significant differences in ADC values of the cerebral hemispheres, basal ganglia, and pons between the single intrauterine fetal death group and either control group.
Although smaller brain biometry was found, normal diffusivity in surviving twins suggests normal parenchymal microstructure. The rate of cerebral structural injury was relatively low in our cohort, arguing against the routine use of fetal brain MR imaging in twin pregnancies complicated with single intrauterine fetal death. Larger prospective studies are necessary to guide appropriate surveillance protocol and parental counseling in twin pregnancies complicated by single intrauterine fetal death.
单胎宫内胎儿死亡会增加存活胎儿的产前脑损伤风险。我们评估了在单胎宫内胎儿死亡后进行的常规妊娠晚期 MRI 检查的存活胎儿中结构脑损伤、脑生物测量和弥散的发生率。
在一项回顾性基于 MRI 的队列研究中，我们比较了 29 例复杂性单绒毛膜双胎妊娠中的单胎宫内胎儿死亡（14 例因双胎输血综合征行激光消融治疗，8 例因选择性胎儿减灭术，7 例为自发性）与 2 个对照组（49 例单胎胎儿和 28 例非复杂性双胎胎儿）。所有单胎宫内胎儿死亡组胎儿均行胎儿脑 MRI 检查作为常规妊娠晚期评估。分析结构脑损伤。测量并比较脑生物测量和弥散。
1 例胎儿发现与先前缺血性损伤演变一致的脑损伤，而这些损伤在超声检查中未被发现。未发现急性脑梗死、出血或皮质异常。单胎宫内胎儿死亡组的幕上脑生物测量值明显小于单胎组，但与非复杂性双胎组无显著差异。单胎宫内胎儿死亡组与对照组之间大脑半球、基底节和脑桥的 ADC 值无显著差异。
尽管脑生物测量值较小，但存活胎儿的弥散正常，提示实质微观结构正常。在我们的队列中，脑结构损伤的发生率相对较低，因此不支持常规在单胎宫内胎儿死亡的双胎妊娠中使用胎儿脑 MRI。需要进行更大的前瞻性研究，以指导适当的监测方案和单胎宫内胎儿死亡的双胎妊娠的父母咨询。
