单绒双胎一胎失活后存活胎儿的脑部发育及妊娠结局差异研究

Brain development and pregnancy outcomes after single fetal demise in mono-chorionic twins

摘要:

目的对比单绒毛膜双胎妊娠中一胎自然死亡(singleton intrauterine death, SIUD)与射频消融减胎术(radiofrequency ablation, RFA)后存活胎儿脑部弥散加权成像的表观弥散系数(apparent diffusion coefficient, ADC)值及妊娠结局的差异。 方法回顾性纳入2022年3月—2024年12月39例SIUD及56例RFA病例，与50例(25对)正常双胎数据进行对照，采用1.5T MRI检测胎儿脑区(额叶、枕叶、小脑等)ADC值，采用独立样本t检验和χ2检验，统计分析两组分娩孕周、出生体重、脑结构异常及产后神经发育数据。 结果RFA组分娩孕周、出生体重显著低于SIUD组(均P<0.001)，早产率(57.1% vs 28.2%)及胎儿生长受限发生率更高；SIUD组存活胎儿死亡率达7.69%(3例)，RFA组无死亡。RFA组左枕叶ADC值显著升高，小脑横径更小，其余脑区差异无统计学意义。3组新生儿入住重症监护室率(RFA组53.6% vs SIUD组62.2% vs 正常组74%)差异无统计学意义(P>0.05)，正常双胎组发育迟缓率较其余两组明显降低(RFA组53.6% vs SIUD组59.0% vs 正常组0%，P<0.001)，产后3个月随访显示短期神经发育结局未见组间差异(P>0.05)，但长期预后仍需进一步评估。 结论SIUD与RFA两组存活胎儿短期神经发育结局相似，但RFA手术可能导致潜在的神经元损伤、RFA组早产风险显著增加，这些发现可为单绒毛膜双胎一胎失活后个体化管理提供关键的影像学依据。

Abstract:

ObjectiveTo compare apparent diffusion coefficient(ADC) values and gestational outcomes in single chorionic twin pregnancies with diffusion-weighted imaging of the brain of the surviving fetus after singleton intrauterine death(SIUD) and radiofrequency ablation(RFA). MethodsThis retrospective analysis evaluated 39 cases of SIUD and 56 cases of RFA from March 2022 to December 2024, 25 pairs of normal twins were set as control. The ADC values of fetal brain regions(frontal lobe, occipital lobe, cerebellum, etc.) were detected by 1.5T MRI. Statistical methods such as independent sample t-test and chi-square analysis were used. The data of gestational weeks at delivery, birth weight, abnormal brain structure and postpartum neurodevelopment of the two groups were statistically analyzed. ResultsCompared with SIUD cases, RFA-treated pregnancies showed significantly earlier delivery(P<0.001), lower birth weights(P<0.001), and higher preterm birth(57.1% vs 28.2%) and fetal growth restriction rates. While SIUD had 7.69% fetal mortality(3 cases), all the RFA cases survived. MRI demonstrated elevated left occipital lobe ADC values(P=0.03) and smaller cerebellar diameters(P<0.001) in RFA group, with no other regional differences. There was no significant differences in the neonatal intensive care unit admission rates among the three groups(RFA group 53.6% vs SIUD group 62.2% vs normal group 74%; P>0.05). The rate of developmental delay was significantly lower in the normal twin group compared to the other two groups(RFA group 53.6% vs SIUD group 59.0% vs normal group 0%; P<0.001). Follow-up at 3 months postpartum showed no intergroup differences in short-term neurodevelopmental outcomes(P>0.05); however, long-term prognosis required further evaluation. ConclusionAlthough short-term neurodevelopmental outcomes are similar in the surviving fetuses in both the SIUD and RFA groups, the RFA procedure may lead to potential neuronal damage, and the risk of preterm birth is significantly increased in the RFA group, the findings provide a critical imaging rationale for the individualized management.