儿童屈光不正性弱视的功能磁共振研究

发布时间：2018-04-15 02:35

本文选题：屈光不正性弱视 + 儿童　；参考：《兰州大学》2011年硕士论文

【摘要】：背景和目的：屈光不正性弱视是一种儿童常见病,其发病本质在于视觉发育的早期,视通路及视皮层未得到相关视觉信号的刺激而导致其功能和结构的改变,影响视觉信息的形成。目前已经有研究证实屈光不正性弱视初级视觉皮层的功能改变,枕叶视觉皮层厚度改变及视辐射、外侧膝状体的功能障碍。高级别视觉皮层是否也存在着功能障碍?分析屈光状态对视皮层的影响,矫正弱视眼屈光不正对视皮层神经元活动有什么影响?弱视视觉皮层功能损害与弱视程度之间的关系怎样?本研究采用血氧水平依赖性功能性磁共振成像(BOLD-fMRI)技术,分析屈光不正性弱视视觉皮层功能的改变情况；矫正屈光不正后,弱视视皮层神经元活动有何改变,弱视眼皮层功能损害与弱视程度是否呈线性相关,可对弱视发病机制及视皮层功能损害有进一步认识。材料与方法：选取2010年07月至2010年8月兰州军区总医院眼科门诊就诊的18例屈光不正性弱视患儿为实验组,18例正常视力儿童志愿者为对照组。采用BOLD-fMRI技术,以SIEMENS AVANTO 1.5T磁共振扫描仪获取图像数据。视觉刺激为自制黑白旋转光栅。实验采用组块设计模式,任务状态组块和控制状态组块分别为旋转光栅和静止光栅,两种组块交替进行。实验组双眼裸眼、双眼屈光矫正分别接受刺激,对照组双眼裸眼接受刺激。实验中T1WI结构图像采用快速自旋回波TSE (Turbo Spin Echo)序列采集。BOLD数据采用平面回波EPI(Echoplanar Imaging)序列采集,三维解剖图像采用磁化准备快速梯度回波MPRAGE(Magnetization Prepared Rapid Gradient Echo)序列采集。受试者完成视觉刺激及数据采集后,将功能激活图像及三维解剖图像Talairach标准化后,进行相关测量及分析。采用本核磁扫描仪自带皮层定位及分析软件,选择枕叶纹状区、纹状旁区及纹周区作为感兴趣区(Region of Interest, ROI)。取ROI激活的总体素数为视觉皮层激活范围。采用SPSS 18.0统计软件,数据用均数±标准差(x±S)表示。对同一弱视受试者裸眼和屈光矫正后皮层激活体素进行两配对样本t检验,弱视即时屈光矫正后皮层的激活体素与对照组皮层激活体素进行两独立样本t检验,不同年龄组弱视即时屈光矫正后皮层的激活体素及对照组皮层激活体素进行两独立样本t检验,对弱视程度与皮层激活体素进行Spearman相关分析,取P0.05为差异有统计学意义。结果：实验组及对照组所有受试者的兴奋区域均位于枕叶视皮层距状裂周围的纹状区、纹状旁区及纹周区。弱视组y|眼视皮层平均激活范围为(9.42±4.22)×103体素,弱视组戴眼镜即时矫正后为(10.57±4.39)×103体素,对照组平均激活体素为(14.30±2.09)×103体素。对弱视组裸眼及弱视组即时屈光矫正后皮层激活体素进行两配对样本t检验(t=-6.524,P=0.00),差异有统计学意义。弱视即时屈光矫正后皮层激活范围明显大于裸眼皮层激活范围。对弱视组即时屈光矫正后和对照组皮层激活体素进行两独立样本t检验(t=3.248,P=0.003),差异有统计学意义,弱视即时屈光矫正后视觉皮层激活范围均明显小于对照组。对不同年龄组皮层激活范围比较发现,4-6岁对照组与即时屈光矫正后皮层激活范围无明显差异(t=0.25,P=0.981),7～8岁与9～岁对照组皮层激活范围大于即时屈光矫正后皮层激活范围(t=2.23,P=0.034,t=-3.626,P=0.002)。对皮层激活体素与弱视程度进行Spearman相关分析,Spearman等级相关系数r=0.181,P=0.472,取P0.05为差异具有统计学意义,故二者无线性相关。结论： 1.屈光不正性弱视视皮层功能有损害。 2.弱视矫正屈光不正后可提高视皮层激活范围,屈光不正性弱视患者应尽早屈光矫正治疗。 3.弱视的皮层功能损害与弱视程度无线性相关,因此临床上的弱视程度分级可能并不能反映皮层功能减弱的情况。
[Abstract]:Background and objective: ametropic amblyopia is a common disease of children, the incidence of early visual development lies in the visual pathway and the visual cortex was not related to visual stimulus signals due to the structural and functional changes, affecting the formation of visual information. There has been change research confirmed ametropia amblyopia with primary visual cortex the function, occipital visual cortex thickness and optic radiation, lateral geniculate body dysfunction. High level visual cortex is also exist dysfunction? Influence analysis of refractive status of visual cortex, what is the effect of correction of ametropia amblyopia visual cortex neuron activity? How the relationship between amblyopia visual cortex function and the degree of amblyopia was used in this study? Blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) technology, analysis of ametropic amblyopia visual cortex function changes. After correction of ametropia, what is the change of neuronal activity in amblyopic visual cortex, and whether the impairment of eyelid function is related to the degree of amblyopia? It can further recognize the pathogenesis of amblyopia and the impairment of visual cortex function.
Materials and methods: 18 cases of ametropia amblyopia from general hospital in 2010 07 months to August 2010 Lanzhou military ophthalmic clinic as the experimental group, 18 cases of normal vision children volunteers as control group. Using BOLD-fMRI technology, image data acquisition based on SIEMENS AVANTO 1.5T magnetic resonance scanner. Visual stimuli for self rotating grating. The experimental group using black and white block design, task state blocks and control state blocks are respectively rotary and stationary grating grating, two blocks alternately. The experimental group binocular uncorrected refractive correction, eyes received stimulation, stimulation of the control group. T1WI binocular uncorrected image using fast spin echo (Turbo TSE Spin Echo.BOLD) sequence acquisition data using echo planar EPI (Echoplanar Imaging) sequence acquisition, 3D anatomical images using a magnetization prepared rapid gradient echo (Magnetization MPRAGE Prepared Rapid Gradient Echo) sequence acquisition. Subjects completed visual stimulation and data acquisition, the function of image and 3D anatomical images of Talairach activation after standardization for measurement and analysis. The MRI scanner with cortical mapping and analysis software, selection of occipital striate area, parastriate area and grain area as a region of interest (Region of, Interest, ROI). The overall prime number ROI for activation of visual cortex activation area. Using SPSS 18 statistical software, data with standard deviation (x + S). On the same amblyopia subjects with naked eye and light correction after flexor cortex activation two paired samples t test, instant amblyopia after refractive correction of cortical activation voxels and cortex activation control group body two independent samples t test, amblyopia in different age groups immediately after refractive correction of cortex activated voxel and the control group was induced into cortex in vivo Two independent sample t test was used to analyze the degree of amblyopia with Spearman of cortical activator, and the difference between P0.05 and amblyopia was statistically significant.
Results: the excited region of the experimental group and control group in all subjects were located in the occipital cortex calcarine area around the parastriate area and peripheral area. Lines of y| in amblyopia eye visual cortex average activation range (9.42 + 4.22) * 103 voxel, amblyopia group prompt corrective glasses after the (10.57 + 4.39) * 103 voxels, the control group mean activated voxel (14.30 + 2.09) x 103 voxels. The naked eye amblyopia group and amblyopia group immediately after refractive correction, cortical activation two paired samples t test (t=-6.524, P=0.00) of elements, the difference was statistically significant. Instant amblyopia after refractive correction, cortical activation was significantly greater than the bare eyelid layer activation range. For instant refractive amblyopia group and control group after cortical activation two independent samples t test elements (t=3.248, P=0.003), the difference was statistically significant, immediate after refractive amblyopia visual cortex activation area was significantly lower than that of control Group. Different age groups of cortical activation range comparison, 4-6 year old control group and immediately after refractive correction, cortical activation had no significant difference (t=0.25, P=0.981), 7~8 years old and 9 years old to control cortical activation than activated cortex instant after refractive correction (t=2.23, P, =0.034, t=-3.626, P=0.002). Cortex voxel Spearman correlated with the degree of amblyopia, Spearman rank correlation coefficient r=0.181, P=0.472, P0.05 as the difference has statistical significance, no linear correlation is two.
Conclusion:
The function of visual cortex in 1. ametropia amblyopia is impaired.
2. amblyopia can improve the range of visual cortex activation after correction of ametropia. The patients with ametropia amblyopia should be treated with refractive correction as soon as possible.
3. the impairment of cortical function in amblyopia has no linear correlation with the degree of amblyopia, so the classification of the degree of amblyopia may not reflect the weakening of cortical function.

【学位授予单位】：兰州大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：R779.7

【引证文献】