Elizabeth Garrett Anderson Institute for Women's Health, University College London, 1st Floor Charles Bell House, 43-45 Foley Street, W1W 7TS, London, UK.
School of Biomedical Engineering & Imaging Sciences (BMEIS), King's College London, London, UK.
Neuroradiology. 2021 Oct;63(10):1721-1734. doi: 10.1007/s00234-021-02725-8. Epub 2021 May 1.
A retrospective study was performed to study the effect of fetal surgery on brain development measured by MRI in fetuses with myelomeningocele (MMC).
MRI scans of 12 MMC fetuses before and after surgery were compared to 24 age-matched controls without central nervous system abnormalities. An automated super-resolution reconstruction technique generated isotropic brain volumes to mitigate 2D MRI fetal motion artefact. Unmyelinated white matter, cerebellum and ventricles were automatically segmented, and cerebral volume, shape and cortical folding were thereafter quantified. Biometric measures were calculated for cerebellar herniation level (CHL), clivus-supraocciput angle (CSO), transverse cerebellar diameter (TCD) and ventricular width (VW). Shape index (SI), a mathematical marker of gyrification, was derived. We compared cerebral volume, surface area and SI before and after MMC fetal surgery versus controls. We additionally identified any relationship between these outcomes and biometric measurements.
MMC ventricular volume/week (mm/week) increased after fetal surgery (median: 3699, interquartile range (IQR): 1651-5395) compared to controls (median: 648, IQR: 371-896); P = 0.015. The MMC SI is higher pre-operatively in all cerebral lobes in comparison to that in controls. Change in SI/week in MMC fetuses was higher in the left temporal lobe (median: 0.039, IQR: 0.021-0.054), left parietal lobe (median: 0.032, IQR: 0.023-0.039) and right occipital lobe (median: 0.027, IQR: 0.019-0.040) versus controls (P = 0.002 to 0.005). Ventricular volume (mm) and VW (mm) (r = 0.64), cerebellar volume and TCD (r = 0.56) were moderately correlated.
Following fetal myelomeningocele repair, brain volume, shape and SI were significantly different from normal in most cerebral layers. Morphological brain changes after fetal surgery are not limited to hindbrain herniation reversal. These findings may have neurocognitive outcome implications and require further evaluation.
本回顾性研究旨在探讨胎儿手术对伴有脊髓脊膜膨出（MMC）胎儿的脑发育的影响，该研究采用 MRI 进行评估。
将 12 例接受胎儿手术的 MMC 胎儿的术前和术后 MRI 扫描与 24 例无中枢神经系统异常的年龄匹配对照组进行比较。采用自动超分辨率重建技术生成各向同性脑体积，以减轻 2D MRI 胎儿运动伪影。自动分割未髓鞘化的白质、小脑和脑室，并定量计算脑容量、形状和皮质折叠。计算小脑疝出水平（CHL）、枢椎颅底角（CSO）、横径小脑直径（TCD）和脑室宽度（VW）的生物测量指标。衍生出脑回形成指数（SI），这是一个衡量脑回形成的数学指标。我们比较了 MMC 胎儿手术前后与对照组之间的脑容量、脑表面积和 SI。此外，我们还确定了这些结果与生物测量指标之间的任何关系。
与对照组相比（中位数：648，IQR：371-896），MMC 胎儿手术后的脑室体积/周（mm/周）增加（中位数：3699，IQR：1651-5395）；P=0.015。与对照组相比，所有脑叶的 MMC SI 术前均较高。MMC 胎儿左颞叶（中位数：0.039，IQR：0.021-0.054）、左顶叶（中位数：0.032，IQR：0.023-0.039）和右枕叶（中位数：0.027，IQR：0.019-0.040）的 SI/周变化高于对照组（P=0.002 至 0.005）。脑室体积（mm）和 VW（mm）（r=0.64）、小脑体积和 TCD（r=0.56）中度相关。
在接受胎儿脊髓脊膜膨出修复后，大多数脑层的脑容量、形状和 SI 与正常情况显著不同。胎儿手术后的形态学脑改变不仅限于后脑疝反转。这些发现可能对神经认知结果有影响，需要进一步评估。
