Abstract：
BACKGROUND: Reduced middle cerebral artery resistance indices (MCA-RI) in fetuses with spina bifida (fSB) are commonly observed. Compression of neuronal pathways in the brainstem due to hindbrain herniation (HH) and disturbed cerebrospinal fluid circulation likely cause an imbalance of the autonomic nervous system. This may increase systemic vasoconstriction and compensatory increase cerebral vasodilation (like brain sparing). The aim of this study was to systematically analyze all fetal MCA-RI before and after fSB repair and to compare their correlation with the presence and postsurgical resolution of HH.
METHODS: 173 patients were included. Standardized ultrasound examinations including MCA and umbilical artery (UA) Doppler as well as assessment of HH presence and regression were performed. Fetuses with MCA-RI <5th percentile (P) before fetal surgery were compared to the group with normal MCA-RI and correlated to the presence of HH before and its regression after fSB repair.
RESULTS: 30% (49/161) fetuses showed RI\'s <5th P before fSB repair. All fetuses had normal UA-RI. 99.4% of fetuses (160/161) showed normal of MCA-RI before delivery. Normalization occurred within a mean of 1.3 ± 1.2 weeks. HH regression was observed in 97% in the group with normal MCA-RI and in 96% in the group with MCA-RI <5th P before surgery (p = 0.59). Time lapse to HH regression after fSB repair was 1.8 ± 1.7 and 1.9 ± 1.6 weeks, respectively.
CONCLUSIONS: In fetuses with MCA-RIs <5 P before fSB repair, a parallel timely course of MCA-RI normalization and HH regression was noted. To suggest common pathogenic factor(s), more studies are needed. However, normalization of the fetal cerebral circulation could be a further benefit of fSB repair.
METHODS: 173 patients were included. Standardized ultrasound examinations including MCA and umbilical artery (UA) Doppler as well as assessment of HH presence and regression were performed. Fetuses with MCA-RI <5th percentile (P) before fetal surgery were compared to the group with normal MCA-RI and correlated to the presence of HH before and its regression after fSB repair.
RESULTS: 30% (49/161) fetuses showed RI\'s <5th P before fSB repair. All fetuses had normal UA-RI. 99.4% of fetuses (160/161) showed normal of MCA-RI before delivery. Normalization occurred within a mean of 1.3 ± 1.2 weeks. HH regression was observed in 97% in the group with normal MCA-RI and in 96% in the group with MCA-RI <5th P before surgery (p = 0.59). Time lapse to HH regression after fSB repair was 1.8 ± 1.7 and 1.9 ± 1.6 weeks, respectively.
CONCLUSIONS: In fetuses with MCA-RIs <5 P before fSB repair, a parallel timely course of MCA-RI normalization and HH regression was noted. To suggest common pathogenic factor(s), more studies are needed. However, normalization of the fetal cerebral circulation could be a further benefit of fSB repair.
摘要：
背景：通常观察到脊柱裂（fSB）胎儿的大脑中动脉阻力指数（MCA-RI）降低。由于后脑疝（HH）和脑脊液循环紊乱，脑干中的神经元通路受压可能会导致自主神经系统失衡。这可能会增加全身血管收缩和代偿性增加脑血管舒张（如脑保留）。这项研究的目的是系统分析fSB修复前后所有胎儿MCA-RI，并比较它们与HH的存在和术后消退的相关性。
方法：纳入173例患者。进行了标准化的超声检查，包括MCA和脐动脉（UA）多普勒，以及对HH的存在和消退的评估。患有MCA-RI的胎儿第5百分位数(P.）将胎儿手术前与MCA-RI正常的组进行比较，并与FSB修复前HH的存在及其消退相关。
结果：30％（49/161）的胎儿在fSB修复前显示RI/s<5thP。所有胎儿的UA-RI正常。99.4%(160/161)的胎儿在分娩前显示MCA-RI正常。标准化发生在平均1.3±1.2周内。在MCA-RI正常的组中观察到97％的HH消退，在MCA-RI＆lt;5thP的组中观察到96％的HH消退。术前（p=0.59）。fSB修复后HH消退的时间分别为1.8±1.7和1.9±1.6周。
结论：在患有MCA-RI的胎儿中<5.P在fSB修理之前，观察到MCA-RI正常化和HH回归的平行及时过程.提示常见致病因素，需要更多的研究。然而,胎儿脑循环的正常化可能是fSB修复的进一步益处。
方法：纳入173例患者。进行了标准化的超声检查，包括MCA和脐动脉（UA）多普勒，以及对HH的存在和消退的评估。患有MCA-RI的胎儿第5百分位数(P.）将胎儿手术前与MCA-RI正常的组进行比较，并与FSB修复前HH的存在及其消退相关。
结果：30％（49/161）的胎儿在fSB修复前显示RI/s<5thP。所有胎儿的UA-RI正常。99.4%(160/161)的胎儿在分娩前显示MCA-RI正常。标准化发生在平均1.3±1.2周内。在MCA-RI正常的组中观察到97％的HH消退，在MCA-RI＆lt;5thP的组中观察到96％的HH消退。术前（p=0.59）。fSB修复后HH消退的时间分别为1.8±1.7和1.9±1.6周。
结论：在患有MCA-RI的胎儿中<5.P在fSB修理之前，观察到MCA-RI正常化和HH回归的平行及时过程.提示常见致病因素，需要更多的研究。然而,胎儿脑循环的正常化可能是fSB修复的进一步益处。
