慢性期脑梗死患者脑灰质和白质结构改变的MRI研究

发布时间：2018-01-28 18:06

本文关键词： 脑梗死基于体素的形态学分析弥散张量成像运动皮层锥体束　出处：《天津医科大学》2014年硕士论文　论文类型：学位论文

【摘要】：目的：采用基于体素的形态学分析(VBM)与弥散张量成像(DTI)方法,研究慢性期脑梗死患者脑灰质和白质的继发性改变及其相关性,为阐明脑梗死后运动功能损伤的内在机制提供理论依据。方法：选择运动功能恢复良好的慢性期单侧基底节区脑梗死患者20例,另选取22名性别、年龄相匹配的健康志愿者作为对照。采用GE3.0T HDX超导型磁共振扫描仪对所有受试者行全脑高分辨率T1WI结构像和DTI扫描。运用SPM8软件包对T1WI结构像数据进行VBM分析。以受试者性别、年龄为协变量,采用两样本t检验在全脑水平比较患者组与对照组灰质体积(GMV)改变的脑区,并以GMV改变脑区作为模板,分别提取每个患者相应脑区GMV值。DTI数据采用FSL4.1软件包进行预处理,追踪双侧锥体束(PT),选取脑桥以上至中央前回皮层下走行的PT进行分析,计算其纤维数量及各弥散指标值(FA值、MD值、λ‖值、λ⊥值),所得数据采用SPSS18.0软件包进行统计学处理,以P0.05作为检验水准。分别比较两组受试者患(右)侧与健(左)侧PT纤维数量和各弥散指标的差异,以及患者组与对照组各相对弥散指标(患[右]侧/健[左]侧)的差异。以每个厘米为一段,将所选区间的双侧PT分为8段,分别比较各节段患者组患侧与健侧各弥散指标的差异,以及患者组与对照组各相对弥散指标的差异。将GMV改变脑区的GMV值与PT总体各相对弥散指标做相关性分析,阐明两者变化趋势。结果： 1、VBM分析结果显示患者组患侧初级运动皮层(M1区)GMV减小(FDR校正P0.05) 2、DTI研究结果显示患者组与对照组健(左)侧PT,总体纤维数量及各弥散指标值比较均无显著差异(P0.05)。与对照组相比,患者组PT总体rNum、rFA值明显减低,rMD、rλ⊥值增高(P0.05) 3、PT分段研究结果显示,患者组患侧PT的第2-7节段FA值较健侧减低,MD值及λ⊥值较健侧增高；第5节段λ‖值较健侧增高(P0.05)。与对照组相比,患者组PT的第3-7节段rFA值减低,rλ⊥值增高；第3-6节段rMD值增高；rλ‖值仅第4、5节段增高(P0.05)。且患侧PT的结构改变以病灶为中心呈顺行性和逆行性扩展。 4、相关分析显示患者组患侧M1区GMV值的改变与PT总体的rFA值呈正相关(R=0.54,P0.05),与rλ⊥上值呈负相关(R=-0.49,P0.05)。结论： 1、基底节区脑梗死患者患侧半球M1区存在GMV减小区域,提示远隔梗死灶的脑皮层灰质也可发生结构损伤。 2、基底节区脑梗死患者患侧PT存在结构损害,这种损害以病灶为中心呈顺行性和逆行性扩展,距离病灶距离越近损伤越严重,距离越远损伤越轻微。 3、PT的逆行性结构损害表现为轴索变性和髓鞘脱失,为远隔梗死灶的脑皮层灰质出现结构损伤的原因。 4、PT的结构损害与脑皮层灰质的结构损害呈正相关,即患侧PT损害越严重,M1区灰质萎缩也越明显。
[Abstract]:Objective: The secondary changes of gray matter and white matter in patients with chronic cerebral infarction were studied by VBM-based morphologic analysis and diffusion Zhang Liang imaging (DTI). To provide theoretical basis for elucidating the intrinsic mechanism of motor function injury after cerebral infarction. Methods: Twenty patients with chronic unilateral basal ganglia infarction with good motor function were selected and 22 patients with sex were selected. Age-matched healthy volunteers were used as controls. GE3.0T was used. HDX superconducting magnetic resonance scanner was used to scan the whole brain of all subjects with high resolution T1WI structure image and DTI. The T1WI structural image data were analyzed by VBM using SPM8 software package. Sex. Age was used as a covariable. Two t-test samples were used to compare the changes of gray matter volume (GMV) between the patient group and the control group at the whole brain level, and the GMV changes were used as a template. The GMV data of each patient's brain region were preprocessed with FSL4.1 software package to track the bilateral pyramidal bundles (PTT). PT from the top of the pons to the subcortical part of the precentral gyrus was selected for analysis, and the number of fibers and the values of each diffusing index (FA) were calculated. The data were processed by SPSS18.0 software package. Using P05 as the test level, the difference of PT fiber quantity and diffusion index between the right side and the healthy side of the two groups were compared, as well as the relative diffusive indexes between the patient group and the control group (P < 0.05). [Right side / health. [Using each centimeter as a segment, the PT of the selected interval was divided into 8 segments, and the diffusive indexes of the affected side and the healthy side were compared respectively. And the difference of relative diffusion index between the patient group and the control group. The correlation analysis was made between the GMV value of the brain area changed by GMV and the relative diffusion index of PT as a whole, and the change trend of the two indexes was clarified. Results: 1) the results of VBM analysis showed that the GMV of the M1 area of primary motor cortex of the affected side of the patients decreased and the correction of FDR was P0.05). 2the results of DTI study showed that there was no significant difference in PTT, total fiber quantity and diffusion index between the patients group and the control group (P 0.05), and compared with the control group (P < 0.05). In the patient group, the total rNumn rFA value was significantly decreased and the rMDN r 位-位 value was increased (P0.05). 3The results of PT segmental study showed that the FA value of segment 2-7 of PT in the patient group was lower than that of the healthy side and the value of MD and 位 Karabakh was higher than that of the healthy side. Compared with the control group, the rFA value of segment 3-7 in the patient group was lower than that in the control group, and the value of r 位 was higher than that in the control group. The rMD value of segment 3-6 was increased. The r位 value was only increased in the 4th and 5th segment (P 0.05), and the structural changes of PT were anterograde and retrograde with the focus as the center. 4. Correlation analysis showed that there was a positive correlation between the change of GMV value in M1 area and the total rFA value of PT (P 0.05). There was a negative correlation between r 位 and the upper value of r 位 _ (-) 0.49% (P _ (0.05)). Conclusion: 1. The decrease of GMV in M1 region of the affected hemispheres in patients with cerebral infarction in basal ganglia region suggests that the cortical gray matter of distant infarct can also occur structural damage. 2. There was structural damage to PT in patients with cerebral infarction in basal ganglia area. The lesion was anterograde and retrograde. The closer the lesion was to the lesion, the more serious the injury was, and the less the distance was. 3The retrograde structural damage of PT was caused by axonal degeneration and demyelination, which was the cause of structural damage in the cortex gray matter of the distant infarct. 4the structural damage of PT was positively correlated with the structural damage of cerebral cortex gray matter, that is, the more serious the PT damage was, the more obvious the gray matter atrophy in M1 area was.
【学位授予单位】：天津医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R743.3;R445.2

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