Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, South Africa; Department of Clinical Research, London School of Hygiene & Tropical Medicine, UK; Neuroscience Institute, University of Cape Town, South Africa.
Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, South Africa.
Neuroimage. 2020 Oct 1;219:116846. doi: 10.1016/j.neuroimage.2020.116846. Epub 2020 Apr 15.
Magnetic resonance imaging (MRI) is an indispensable tool for investigating brain development in young children and the neurobiological mechanisms underlying developmental risk and resilience. Sub-Saharan Africa has the highest proportion of children at risk of developmental delay worldwide, yet in this region there is very limited neuroimaging research focusing on the neurobiology of such impairment. Furthermore, paediatric MRI imaging is challenging in any setting due to motion sensitivity. Although sedation and anesthesia are routinely used in clinical practice to minimise movement in young children, this may not be ethical in the context of research. Our study aimed to investigate the feasibility of paediatric multimodal MRI at age 2-3 years without sedation, and to explore the relationship between cortical structure and neurocognitive development at this understudied age in a sub-Saharan African setting. A total of 239 children from the Drakenstein Child Health Study, a large observational South African birth cohort, were recruited for neuroimaging at 2-3 years of age. Scans were conducted during natural sleep utilising locally developed techniques. T1-MEMPRAGE and T2-weighted structural imaging, resting state functional MRI, diffusion tensor imaging and magnetic resonance spectroscopy sequences were included. Child neurodevelopment was assessed using the Bayley-III Scales of Infant and Toddler Development. Following 23 pilot scans, 216 children underwent scanning and T1-weighted images were obtained from 167/216 (77%) of children (median age 34.8 months). Furthermore, we found cortical surface area and thickness within frontal regions were associated with cognitive development, and in temporal and frontal regions with language development (beta coefficient ≥0.20). Overall, we demonstrate the feasibility of carrying out a neuroimaging study of young children during natural sleep in sub-Saharan Africa. Our findings indicate that dynamic morphological changes in heteromodal association regions are associated with cognitive and language development at this young age. These proof-of-concept analyses suggest similar links between the brain and cognition as prior literature from high income countries, enhancing understanding of the interplay between cortical structure and function during brain maturation.
磁共振成像（MRI）是研究幼儿大脑发育和发育风险与弹性的神经生物学机制的不可或缺的工具。撒哈拉以南非洲地区是全世界儿童发育迟缓风险最高的地区，但在该地区，针对此类损伤的神经生物学研究非常有限。此外，由于对运动敏感，儿科 MRI 成像在任何环境下都具有挑战性。尽管在临床实践中常规使用镇静和麻醉来最小化幼儿的运动，但在研究背景下，这可能不符合伦理规范。我们的研究旨在调查在没有镇静的情况下，2-3 岁儿童进行儿科多模态 MRI 的可行性，并探索在撒哈拉以南非洲地区这个研究较少的年龄段，皮质结构与神经认知发育之间的关系。共有 239 名来自 Drakenstein 儿童健康研究的儿童参加了神经影像学检查，这是一项大型南非出生队列的观察性研究。扫描在自然睡眠期间进行，利用当地开发的技术。包括 T1-MEMPRAGE 和 T2 加权结构成像、静息态功能 MRI、弥散张量成像和磁共振波谱序列。使用贝利婴幼儿发育量表评估儿童神经发育情况。在进行了 23 次试点扫描后，216 名儿童进行了扫描，其中 167/216（77%）名儿童获得了 T1 加权图像（中位数年龄为 34.8 个月）。此外，我们发现额叶区域的皮质表面积和厚度与认知发育有关，而在颞叶和额叶区域与语言发育有关（β系数≥0.20）。总的来说，我们证明了在撒哈拉以南非洲地区，在自然睡眠期间对幼儿进行神经影像学研究是可行的。我们的研究结果表明，异模态联合区域的动态形态变化与这个年龄段的认知和语言发育有关。这些概念验证分析表明，大脑和认知之间存在类似的联系，与高收入国家的先前文献一致，增强了对大脑成熟过程中皮质结构和功能相互作用的理解。
