Horská Alena, Kaufmann Walter E, Brant Larry J, Naidu Sakkubai, Harris James C, Barker Peter B
The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205, USA.
J Magn Reson Imaging. 2002 Feb;15(2):137-43. doi: 10.1002/jmri.10057.
To quantify regional variations in metabolite levels in the developing brain using quantitative proton MR spectroscopic imaging (MRSI).
Fifteen healthy subjects three to 19 years old were examined by in vivo multislice proton MRSI. Concentrations of N-acetyl aspartate (NAA), total choline (Cho), total creatine (Cr), and peak area ratios were determined in selected frontal and parietal gray and white matter regions, basal ganglia, and thalamus.
In cortical gray matter regions, the ratio of NAA/Cho increased to a maximum at 10 years and decreased thereafter (P = 0.010). In contrast, in white matter, average ratios NAA/Cho increased linearly with age (P = 0.045). In individual brain regions, age-related changes in NAA/Cho were found in the putamen (P = 0.044). No significant age-related changes in NAA, Cho, Cr, or other metabolite ratios could be determined.
Consistent with recent studies using other structural and functional neuroimaging techniques, our data suggest that small but significant changes occur in regional cerebral metabolism during childhood and adolescence. Non-linear age related changes of NAA/Cho in frontal and parietal areas, resembling previously reported age related changes in rates of glucose utilization and cortical volumes, may be associated with dendritic and synaptic development and regression. Linear age-related changes of NAA/Cho in white matter are also in agreement with age-related increases in white matter volumes, and may reflect progressive increases in axonal diameter and myelination.
使用定量质子磁共振波谱成像（MRSI）量化发育中大脑代谢物水平的区域差异。
对15名3至19岁的健康受试者进行了活体多层质子MRSI检查。在选定的额叶和顶叶灰质和白质区域、基底神经节和丘脑中测定了N-乙酰天门冬氨酸（NAA）、总胆碱（Cho）、总肌酸（Cr）的浓度以及峰面积比。
在皮质灰质区域，NAA/Cho比值在10岁时升至最高，此后下降（P = 0.010）。相比之下，在白质中，NAA/Cho的平均比值随年龄呈线性增加（P = 0.045）。在各个脑区中，壳核发现了NAA/Cho与年龄相关的变化（P = 0.044）。未发现NAA、Cho、Cr或其他代谢物比值与年龄相关的显著变化。
与最近使用其他结构和功能神经成像技术的研究一致，我们的数据表明，儿童期和青春期大脑区域代谢发生了虽小但显著的变化。额叶和顶叶区域NAA/Cho的非线性年龄相关变化，类似于先前报道的葡萄糖利用率和皮质体积的年龄相关变化，可能与树突和突触的发育及退化有关。白质中NAA/Cho的线性年龄相关变化也与白质体积的年龄相关增加一致，可能反映了轴突直径和髓鞘形成的逐渐增加。
