Noninvasive evaluation of the regional variations of GABA using magnetic resonance spectroscopy at 3 Tesla
Noninvasive evaluation of the regional variations of GABA using magnetic resonance spectroscopy at 3 Tesla
复制标题
DOI：
10.1016/j.mri.2015.02.015
复制
发表时间：
2015-06-01
影响因子：
2.5
通讯作者：
Velan, S. Sendhil
中科院分区：
文献类型：
--
作者：
Durst, Christopher R.;Michael, Navin;Velan, S. Sendhil
目的：GABA的快速区域波动可能导致整个脑实质中的浓度不均匀。本研究的目的是进一步了解GABA在整个大脑中的自然分布，从而确定在评估运动疾病、神经系统疾病或精神功能障碍时，是否可以使用替代位点进行光谱分析。材料和方法：在这项前瞻性研究中，8名健康志愿者接受了额叶、枕叶、侧颞叶、基底神经节，以及使用J-差分编辑方法的自旋回波变体的两个双标度。使用3 ppm和0.9 ppm处大分子峰的相对峰强度的知识来校正共同编辑的大分子对3 ppm处GABA峰的贡献。GABA值内部参考NAA。线性回归被用来规范化的GABA/NAA值的区域组织分数的变化的影响。采用Tukey多重比较检验进行单因素方差分析，以比较每对位置的标准化GABA/NAA值。结果：在考虑了大分子对GABA信号的贡献和组织分数变化的校正后，标准化GABA/NAA比率在六个脑位置之间存在显著差异（p < 0.001）。校正后的标准化GABA/NAA比值的成对比较显示额叶和基底节、额叶和侧颞叶以及额叶和右侧海马之间存在统计学显著性差异。额叶与左侧海马、枕叶与额叶、枕叶与基底节、枕叶与右侧海马之间GABA/NAA比值的变化有显著性差异。评价GABA作用的研究在结合光谱学时必须仔细考虑体素的位置。(C)2015 Elsevier Inc. All rights reserved.
Purpose: Rapid regional fluctuations in GABA may result in inhomogeneous concentrations throughout the brain parenchyma. The goal of this study is to provide further insight into the natural distribution of GABA throughout the brain and thus determine if a surrogate site may be used for spectroscopy when evaluating motor diseases, neurological disorders, or psychiatric dysfunction.Materials and Methods: In this prospective study, eight healthy volunteers underwent spectroscopic evaluation of the frontal lobe, occipital lobe, lateral temporal lobe, basal ganglia, and both hippocampi using a spin echo variant of a J-difference editing method. Knowledge of the relative peak intensities of the macromolecule peaks at 3 ppm and 0.9 ppm was used to correct the contribution of co-edited macromolecules to the GABA peak at 3 ppm. The GABA values were internally referenced to NAA. Linear regression was used to normalize the effect of regional tissue-fraction variation on the GABA/NAA values. A one-way ANOVA was performed with Tukey's multiple comparison test to compare the normalized GABA/NAA values in each pair of locations.Results: After accounting for the macromolecule contribution to the GABA signal and correction for tissue fraction variation, the normalized GABA/NAA ratios differ significantly between the six brain locations (p < 0.001). Pairwise comparisons of the corrected normalized GABA/NAA ratios show statistically significant variation between the frontal lobe and the basal ganglia, frontal and lateral temporal lobes, and frontal lobe and right hippocampus. Variations in the normalized GABA/NAA ratios trend toward significance between the frontal lobe and left hippocampus, occipital lobe and the frontal lobe, occipital lobe and basal ganglia, and occipital lobe and right hippocampus.Conclusion: Our study suggests that GABA concentration is inhomogeneous throughout the parenchyma. Studies evaluating the role of GABA must carefully consider voxel placement when incorporating spectroscopy. (C) 2015 Elsevier Inc. All rights reserved.