Centre for Medical Image Computing (CMIC), University College London, UK.
Academic Neonatology, EGA UCL Institute for Women's Health, London, UK.
Neuroimage. 2014 Apr 1;89:23-34. doi: 10.1016/j.neuroimage.2013.11.048. Epub 2013 Dec 6.
The survival rates of infants born prematurely have improved as a result of advances in neonatal care, although there remains an increased risk of subsequent disability. Accurate measurement of the shape and appearance of the very preterm brain at term-equivalent age may guide the development of predictive biomarkers of neurological outcome. We demonstrate in 92 preterm infants (born at an average gestational age of 27.0±2.7weeks) scanned at term equivalent age (scanned at 40.4±1.74weeks) that the cortical sulcation ratio varies spatially over the cortical surface at term equivalent age and correlates significantly with gestational age at birth (r=0.49,p<0.0001). In the underlying white matter, fractional anisotropy of local white matter regions correlated significantly with gestational age at birth at term equivalent age (for the genu of the corpus callosum r=0.26,p=0.02 and for the splenium r=0.52,p<0.001) and in addition the fractional anisotropy in these local regions varies according to location. Finally, we demonstrate that connectivity measurements from tractography correlate significantly and specifically with the sulcation ratio of the overlying cortical surface at term equivalent age in a subgroup of 20 infants (r={0.67,0.61,0.86}, p={0.004,0.01,0.00002}) for tract systems emanating from the left and right corticospinal tracts and the corpus callosum respectively). Combined, these results suggest a close relationship between the cortical surface phenotype and underlying white matter structure assessed by diffusion weighted MRI. The spatial surface pattern may allow inference on the connectivity and developmental trajectory of the underlying white matter complementary to diffusion imaging and this result may guide the development of biomarkers of functional outcome.
早产儿的存活率因新生儿护理的进步而提高，尽管随后残疾的风险仍然增加。在相当于胎龄的足月时准确测量极早产儿脑的形状和外观，可能有助于预测神经结局的生物标志物的发展。我们在 92 名早产儿（平均胎龄为 27.0±2.7 周）中进行了研究，这些早产儿在相当于胎龄的足月时进行了扫描（扫描时为 40.4±1.74 周），结果表明皮质脑回比在相当于胎龄的足月时在皮质表面上具有空间变化，并与出生时的胎龄显著相关（r=0.49，p<0.0001）。在基础白质中，局部白质区域的各向异性分数与相当于胎龄的足月时的胎龄显著相关（胼胝体膝部 r=0.26，p=0.02，而压部 r=0.52，p<0.001），此外，这些局部区域的各向异性分数也根据位置而变化。最后，我们证明在 20 名婴儿的亚组中（r={0.67,0.61,0.86}，p={0.004,0.01,0.00002}），来自左右皮质脊髓束和胼胝体的束路追踪的连通性测量值与相当于胎龄的皮质表面脑回比显著且特异性相关。综合这些结果表明，扩散加权 MRI 评估的皮质表面表型与基础白质结构之间存在密切关系。空间表面模式可以根据连通性和基础白质的发育轨迹进行推断，这与扩散成像互补，并且该结果可能有助于功能结局生物标志物的开发。
