3T磁共振DTI和BOLD成像对慢性高原病脑结构和功能的研究

发布时间：2018-10-23 12:35

【摘要】：目的：利用3.0T超高场强静息态血氧水平依赖功能磁共振成像（Blood-oxygenlevel dependent fMRI, BOLD-fMRI）和扩散张量成像（Diffusion tensor imaging,DTI）技术，研究慢性高原病（Chronic Mountain Sickness, CMS）患者自发脑活动特征和白质结构特征，探讨慢性缺氧对脑结构和功能的影响。研究方法：对13例临床确诊的CMS患者和12例性别、年龄、受教育程度及居住海拔高度相匹配的正常自愿者（对照组）进行静息态BOLD和DTI磁共振成像扫描。采用局部一致性（Regional Homogeneity, ReHo）方法处理BOLD数据，对CMS组和对照组静息态下大脑的自发活动进行对比分析。采用基于纤维束的空间统计方法（Tract-Based Spatial Statistics,TBSS）分析DTI数据，计算CMS组和对照组脑白质的各向异性参数（包括部分各向异性（FractionalAnisotropy,FA）、平均弥散系数（Mean Diffusivit, MD）、轴向弥散系数（Axial diffusivity, AD）和径向弥散系数（Radial diffusivity, RD））。采用基于体素的单样本t检验对BOLD组内数据进行比较，采用基于体素的两样本t检验进行BOLD数据的组间比较。采用基于体素的两样本t检验进行DTI数据的组间比较。结果：1.ReHo分析结果：①在静息状态下CMS组和对照组都表现出多个脑区激活，分布区域大体一致，但CMS组总体的局部神经元活动一致性程度比对照组相对降低；②与对照组相比，CMS组在双侧颞下回、右侧梭状回和左侧额中回ReHo减低，在左侧海马旁回、左侧中央后回ReHo增高，差异有统计学意义（p0.01，，alphasim校正）。2.DTI分析结果：①与对照组比较，CMS组在小脑表现出较低的MD（p0.01，未校正），在小脑和胼胝体压部表现出较低的AD（p0.01，未校正）；②与对照组相比，CMS组无任何脑区表现出明显增高的FA、MD、AD和RD（p 0.01，未校正）。结论：CMS组和对照组在静息状态下大脑局部一致性存在一定的差异；两组之间大脑白质的各向异性参数也存在特异性差异，这些结构和功能的差异可以帮助我们深入地了解慢性缺氧对大脑的影响。
[Abstract]:Objective: to study the characteristics of spontaneous brain activity and white matter structure in patients with chronic high altitude disease (Chronic Mountain Sickness, CMS) by using 3.0T ultra-high field resting blood oxygen level dependent functional magnetic resonance imaging (Blood-oxygenlevel dependent fMRI, BOLD-fMRI) and diffusion imaging (Diffusion tensor imaging,DTI). To investigate the effect of chronic hypoxia on brain structure and function. Methods: 13 patients with clinically diagnosed CMS and 12 normal volunteers (control group) matched with sex, age, education level and residence altitude were scanned by resting BOLD and DTI MRI. Local consistent (Regional Homogeneity, ReHo) method was used to process BOLD data and the brain spontaneous activity in CMS group and control group was analyzed. The spatial statistical method based on fiber bundle (Tract-Based Spatial Statistics,TBSS) was used to analyze DTI data. Calculate the anisotropic parameters of white matter (including partial anisotropy (FractionalAnisotropy,FA), mean diffusion coefficient (Mean Diffusivit, MD), axial diffusion coefficient (Axial diffusivity, AD) and radial diffusion coefficient (Radial diffusivity, RD).) of white matter in CMS group and control group) A single sample t test based on voxel was used to compare the data in BOLD group and two samples t test based on voxel was used to compare BOLD data between groups. Two samples t test based on voxel were used to compare DTI data. Results: the results of 1.ReHo analysis were as follows: (1) in the rest state, the CMS group and the control group showed multiple brain activation, and the distribution areas were roughly the same, but the consistency degree of the local neuronal activity in the CMS group was lower than that in the control group. 2Compared with the control group, ReHo in bilateral infratemporal gyrus, right fusiform gyrus and left middle frontal gyrus decreased in CMS group, but increased in left parahippocampal gyrus and left postcentral gyrus. The results of 2.DTI analysis were as follows: 1 compared with control group, CMS group showed lower MD in cerebellum (p0.01, uncorrected), lower AD in cerebellum and corpus callosum (p0.01, uncorrected); 2 compared with the control group, there was no significant increase in FA,MD,AD and RD (p in the CMS group. Conclusion: there are some differences between the CMS group and the control group in the regional consistency of the brain, the anisotropy parameters of the white matter in the brain are also different between the two groups, and there is also a specific difference between the two groups. These differences in structure and function can help us understand the effects of chronic hypoxia on the brain.
【学位授予单位】：青海大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R445.2;R594.3

【参考文献】