婴幼儿发育迟缓的功能磁共振成像初步研究

发布时间：2018-04-21 14:13

本文选题：发育迟缓 + 婴幼儿　；参考：《南方医科大学》2017年硕士论文

【摘要】：研究目的:通过静息态血氧水平依赖脑功能成像(blood oxygenation level dependent functional magnetic imaging,BOLD-fMRI)和磁共振扩散张量成像(diffusion tensor imaging,DTI)技术观察无明确病因的发育迟缓(global developmental delay,GDD)婴幼儿静息状态下局部脑区神经活动改变和脑白质微细结构改变,探讨婴幼儿发育迟缓的脑损伤模式,为早期诊断婴幼儿发育迟缓提供影像学指标。材料与方法:我们选用22例Bayley婴幼儿发育量表评分低于69分的发育迟缓婴幼儿作为病例组。同时选择14例年龄、性别等与之无明显统计学差异的发育正常婴幼儿作为对照组。病例组和对照组婴幼儿均接受磁共振检查,包括常规磁共振扫描序列(横轴位T1WI、T2WI、FLAIR),静息态BOLD-fMRI扫描序列及DTI扫描序列,扫描范围包括全部大脑,排除在常规磁共振扫描序列中有异常影像学表现的婴幼儿。应用局部一致性(regional homogeneity,ReHo)和低频振幅(amplitude of low frequency fluctuation,ALFF)分析 GDD 婴幼儿组和发育正常婴幼儿组的RS-fMRI数据,评估GDD婴幼儿静息状态下局部脑区神经活动改变情况。采用基于纤维束示踪的空间统计分析(tract-based spatial statistics,TBSS)方法分析GDD婴幼儿组和足月发育正常婴幼儿组的DTI数据,比较分析GDD婴幼儿与发育正常婴幼儿全脑白质的各向异性分数(fractional anisotropy,FA)值和平均扩散率(mean diffusivity,MD)值的变化特点,寻找有显著性差异的脑白质纤维。结果:相对于发育正常婴幼儿组,GDD婴幼儿组ALFF值减小脑区包括左侧颞中回和右侧扣带回;ALFF值增加脑区为楔前叶。与发育正常婴幼儿组相比,GDD婴幼儿组脑前额叶ReHo值减低;ReHo值增加的脑区为右侧大脑半球额上回。与发育正常婴幼儿组相比,GDD婴幼儿组多个脑区纤维束FA值显著减小,主要包括双侧放射冠区,右侧内囊前肢,右侧矢状层、额上皮层及梭状回附近,左侧穹窿、上纵束、内囊晶状体后侧及小脑脚上部等部位的纤维束;右侧上纵束FA值增加。对比发育正常婴幼儿组,发育迟缓婴幼儿白质纤维束MD值增高的脑区包括:左侧小脑、小脑脚中部和小脑蚓部,右侧梭状回和内侧丘脑;左侧楔叶部位的白质纤维束MD值减小。结论:与发育正常婴幼儿相比,发育迟缓婴幼儿的局部大脑皮层功能和脑白质纤维束微结构有其特殊性,这种特殊性可能与该病的病理基础有关。研究婴幼儿发育迟缓的功能神经影像学改变,有助于了解其发病机制,从而为其提供早期诊断的影像学指标。
[Abstract]:Objective: to observe the regional brain regions in infants with global developmental delay-GDDs without definite etiology by resting blood oxygenation level dependent functional magnetic imaging1 (BOLD-f MRI) and diffusion Zhang Liang diffusion tensor imaging (DTI) techniques. Changes in nerve activity and microstructures in the white matter, To explore the model of brain injury in infants with developmental retardation, and to provide imaging index for early diagnosis of infant stunting. Materials and methods: 22 cases of stunted infants with Bayley score below 69 were selected as the case group. At the same time, 14 normal infants with age and sex were selected as control group. All infants and infants in the case group and the control group underwent MRI examination, including conventional MRI sequences (axial T1WIT T2WIFLAIRI, resting BOLD-fMRI scan sequence and DTI scan sequence). The scanning range included all the cerebrum, the brain, brain, brain, brain, brain, brain, brain, brain, brain, brain, brain, brain, brain and brain. Infants excluded from conventional MRI sequences with abnormal imaging findings. The regional homogenicity (ReHoA) and low frequency amplitude amplitude of low frequency structure (ALFF) were used to analyze the RS-fMRI data of GDD infants and normal infants, and to evaluate the changes of regional brain nerve activity in GDD infants. The spatial statistical analysis based on tracer of fiber bundle was used to analyze the DTI data of GDD infants and infants with normal term development. The characteristics of anisotropic fraction (FA) and mean diffusivity (MD) of white matter in the whole brain of GDD infants and normal infants were compared and analyzed, and the white matter fibers with significant difference were found. Results: compared with normal infant group, ALFF decreased cerebellar area including left middle temporal gyrus and right cingulate gyrus. Compared with normal infant group, the prefrontal lobe ReHo decreased and ReHo increased in the right hemisphere superior frontal gyrus. Compared with normal infant group, the FA value of fibrous bundles in GDD group decreased significantly, including bilateral radio-coronal area, right anterior limb of internal capsule, right sagittal layer, frontal cortex and near fusiform gyrus, left fornix, superior longitudinal bundle. The fiber bundle in the posterior side of the internal capsule lens and the upper part of the cerebellar foot increased the FA value of the right superior longitudinal bundle. Compared with normal infant group, the areas with increased MD value of white matter fiber bundle in stunted infants included left cerebellum, middle cerebellar foot and cerebellar vermis, right fusiform gyrus and medial thalamus, and decreased MD of white matter fiber bundle in left wedge lobe. Conclusion: compared with normal infants, the local cerebral cortex function and white matter fiber bundle microstructures of stunted infants have their particularities, which may be related to the pathological basis of the disease. The study of functional neuroimaging changes in infants with developmental retardation is helpful to understand its pathogenesis and to provide early diagnostic imaging indicators.
【学位授予单位】：南方医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R445.2;R749.94

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