正常脑老化中海马亚区静息态功能连接的磁共振研究

发布时间：2018-05-19 14:33

本文选题：静息态 + 功能磁共振成像　；参考：《河北医科大学》2017年硕士论文

【摘要】：目的:当今社会人口老龄化问题日益严峻,众多学者对脑老化展开了广泛而深入的研究。脑老化与大脑结构、功能密切相关。认知功能减退是脑老化的重要标志,认知功能减退不仅影响老年人的生活质量,还给其家庭及社会带来沉重负担。海马是参与认知的重要脑结构,由功能不同亚区组成。近年来有不少研究者对脑老化中海马的形态学改变进行研究,已深入到亚区水平。静息态BOLD-fMRI功能连接研究侧重于不同脑区间的相互联系,从宏观层面探索整个大脑运行机制。研究证实脑老化中存在静息态功能连接的改变,但是脑老化中海马亚区的静息态功能连接改变尚不清楚。本研究基于静息态功能磁共振成像,研究中老年组和年轻组之间静息状态下海马亚区与全脑功能连接的差异,进而阐明脑老化中海马亚区功能连接的变化及其意义。方法:将符合纳入标准的121名志愿者,按年龄分为两组:年轻组60名,其中男性23例,女性37例,年龄范围22-31岁,平均年龄26.15±1.9岁;中老年组61人,男性23例,女性38例,年龄范围45-65岁,平均年龄52.6±5.9岁。采用GE公司Signa Excite 3.0T超导型磁共振扫描仪均行常规序列检查,然后采集静息态功能磁共振图像。扫描线圈为标准8通道头颅线圈。受试者仰卧于扫描床上,为了减少头动,头部用海绵垫固定。扫描前嘱受试者保持清醒、睁眼、呈放松状态,且尽量不作任何系统性思考。采用基于Matlab的DPARSFA软件对高分辨率静息态功能磁共振数据进行预处理。应用目前静息态功能连接分析中最简单也是最常用的基于感兴趣区的分析法来研究正常老化中海马亚区的功能连接改变。根据SPM Anatomy toolbox提取海马亚区(双侧CA1,CA2,CA3,DG,SUB)。选择海马亚区中10个种子点,提取所有种子点的平均时间序列,分别进行种子点与全脑其他体素的功能连接计算。应用SPM对两组全脑区域的时间相关性图像进行两样本T检验的统计分析。将经过两样本T检验的海马亚区功能连接结果分别叠加在REST自带的Ch2 bet图像上进行显示。观察中老年组和年轻组静息状态下的海马亚区功能连接是否存在差异(P0.01),Alphasim校正。观察有统计学意义的活动团块的脑区定位、MNI坐标、团块的大小,并观察其t值。结果:所有图像均符合标准。1中老年组与年轻组相比较,与CA1区功能连接减低的脑区主要有右侧岛盖部额下回,与CA1区功能连接增加的脑区主要有右侧额上回及左侧额中回(Fig.1)。2中老年组与年轻组相比较,与CA2区功能连接减低的脑区主要有右侧海马及左侧豆状核,与CA2区功能连接增加的脑区主要有右侧额上回、左侧额中回、右侧颞下回、左侧颞中回(Fig.2)。3中老年组与年轻组相比较,与CA3区功能连接减低的脑区主要有左侧海马,与CA3区功能连接增加的脑区主要有左侧额中回(Fig.3)。4中老年组与年轻组相比较,与DG区功能连接减低的脑区主要有右侧岛盖部额下回,与DG区功能连接增加的脑区主要为左侧额中回(Fig.4)。5中老年组与年轻组相比较,与SUB区功能连接减低的脑区主要有右侧岛盖部额下回及左侧海马旁回,与SUB区功能连接增加的脑区主要有右侧额上回(Fig.5)。结论:1在正常脑老化过程中,海马不是均一的老化,不同亚区具有各自特征。2与年轻组相比,中老年组中与海马亚区功能连接减低的脑区主要有右侧岛盖部额下回,与海马亚区功能连接增加的脑区主要有右侧额上回及左侧额中回。3关于海马的老化现象,功能连接降低可能与认知功能下降有关,功能连接增加可能是对认知功能下降的补偿。
[Abstract]:Objective: the problem of aging population is becoming more and more serious in today's society. Many scholars have conducted extensive and deep research on brain aging. Brain aging is closely related to brain structure and function. Cognitive impairment is an important sign of brain aging. Cognitive impairment not only affects the living quality of the elderly, but also brings a heavy burden to the family and the society. Hippocampus is an important brain structure involved in cognition, which is composed of different functional subregions. In recent years, many researchers have studied the morphological changes of the hippocampus in the brain aging, which has gone deep into subregion level. The resting state BOLD-fMRI function connection research focuses on the interrelation of different brain regions and explores the whole brain operation mechanism from the macro level. The study confirms the change of resting state function connection in brain aging, but it is not clear that the resting state function connection of brain aging is not clear. This study is based on resting state functional magnetic resonance imaging (fMRI) to study the differences in the connection between the hippocampus and the whole brain in the resting state between the elderly and the young groups, and then to clarify the aging of the brain. The changes and significance of the functional connection of Maya district. Methods: 121 volunteers were divided into two groups according to the age of inclusion: 60 in the young group, of which 23 were male, 37 women, 22-31 years of age, and the average age was 26.15 + 1.9 years; middle and old age group 61, 23 males, 38 cases, age 45-65 years, average age 52.6 + 60 years old. E's Signa Excite 3.0T superconducting magnetic resonance scanner all performed routine sequence examination and then collected resting functional magnetic resonance images. The scanning coil was a standard 8 channel head coil. The subjects were lying on the scanning bed. In order to reduce head motion, the head was fixed with a sponge pad. Matlab based DPARSFA software is used to preprocess high resolution resting state functional magnetic resonance data. The simplest and most commonly used region based analysis method based on interest zone analysis in the current resting state function analysis is used to study the functional connection changes in the hippocampus subregion of normal aging. According to SPM Anatom Y toolbox extraction of hippocampal subregion (bilateral CA1, CA2, CA3, DG, SUB). Select the 10 seed points in the subregion of the hippocampus, extract the average time sequence of all the seed points, and calculate the function connection between the seed points and the whole brain other voxels respectively. The statistical analysis of the time phase image of the two groups of whole brain regions by SPM is used to analyze the statistical analysis of the two sample T test. The results of the functional connectivity of the hippocampal subregion of the two sample T test were superimposed on the REST Ch2 bet images respectively. The differences in the functional connectivity of the hippocampus subregion in the middle and old age group and the young group were observed (P0.01) and Alphasim correction. The brain location, MNI coordinates, and the size of the group were observed with statistical significance. The T value. Results: all images were in accordance with the standard.1 in the elderly group compared with the young group. The brain areas with the functional connection with the CA1 area were mainly lower than the right side of the island cover. The brain areas with the function connection with the CA1 area were mainly the right upper frontal gyrus and the left middle frontal gyrus (Fig.1).2 in the elderly group compared with the young group, and the function connection with the CA2 region. The brain regions of the reduced brain were mainly right hippocampal and left-sided lenticular nucleus. The brain areas with the functional connection with CA2 area were mainly right frontal gyrus, left middle frontal gyrus, right temporal gyrus, and left temporal gyrus (Fig.2).3, compared with the young group, the brain area with the function connection with CA3 area was mainly left hippocampus, and the function connection with CA3 area increased. Compared with the young group in the middle frontal middle frontal gyrus (Fig.3).4, the brain area with the function connection with the DG area was mainly lower than that of the right Island, and the brain area with the function connection with the DG region was mainly the left middle frontal gyrus (Fig.4).5 in the middle aged group and the young group, and the brain area with the functional connection of the SUB region was mainly on the right island. The lower frontal gyrus and the left parahippocampal gyrus were mainly in the right frontal gyrus (Fig.5) in the functional connection with the SUB area. Conclusion: 1 in the normal aging process, the hippocampus is not homogeneous, and the different subregions have their respective characteristics.2, compared with the young group, the brain areas with lower functional connectivity in the middle and old age group are mainly the right Island cover. In the lower frontal gyrus, the brain regions with the functional connection with the hippocampal subregion mainly include the aging of the right frontal upper frontal gyrus and the left middle frontal gyrus (.3). The decrease of functional connection may be related to the decline of cognitive function, and the increase of functional connection may be the compensation for the decline of cognitive function.
【学位授予单位】：河北医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R445.2

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