屈光参差性弱视儿童视觉运动功能损害的功能磁共振成像研究
发布时间：2018-08-29 15:03
【摘要】：[目的]利用血氧水平依赖性功能磁共振成像(BOLD-fMRI)技术对屈光参差性弱视儿童在视觉运动刺激时大脑皮层反应进行观察,研究屈光参差性弱视的视觉运动功能受到的影响,分析皮层激活改变与视力损害间的可能关系。 [方法]采用BOLD-fMRI技术及组块设计模式,以1.5T磁共振成像系统扫描图像获取数据。实验刺激程序采用神经心理学编程软件"Presention"。刺激任务为注视水平左向、右向移动垂直正弦光栅,空间频率为5cycle/degree(c/d),移动速度为4°/sec,对比度为50%,周边对比度逐渐减低以消除明显的边缘,基底任务为注视固定于刺激屏中央的白色“+”点。从我院眼科门诊连续抽取屈光参差性弱视组患者25例,剔除头动与运动伪影后,共20例,其中男11例,女9例,年龄6-15岁；正常对照组25例,剔除头动与运动伪影后,共23例,其中男11例,女12例,年龄6-14岁。实验前均行散瞳验光及试镜,实验组与对照组均无其它严重眼部疾病及神经系统疾病,无全身疾病史。BOLD数据采集采用EPI (Echo Planar Imaging)序列,三维解剖图像采集采用3D-FSPGR序列作矢状位薄层扫描。受试者完成视觉任务及数据采集后,应用AFNI、Matlab、SPM5软件进行数据处理和统计分析。预处理包括时间矫正、头动矫正、空间标准化及三维空间平滑处理等。经过预处理后,对符合要求的受试者数据进行统计分析。通过时间信号强度曲线的相关分析来判断与刺激和对照任务之间差异直接相关的激活区。然后对资料进行像素水平的t检验,筛选脑激活区。分析包括：1、对正常对照组左、右眼间刺激进行SPM5基本模型配对t检验。2、对屈光参差性弱视组的弱视眼、对侧眼及正常对照组左眼、右眼进行组分析,获取平均激活图。3、对屈光参差性弱视儿童的弱视眼、对侧眼和对照组刺激脑激活区及激活强度分别进行组间比较。4、弱视眼皮层神经元损害情况与视力损害情况的关系。 [结果]①正常对照组左、右眼刺激激活最明显的区域为中颞区(MT区)、Brodmann37和19区即中、下颞叶及中枕叶,其次为Brodmann17区、18区即舌回、楔状回、楔前叶皮层,此外尚有小脑后叶、顶上小叶等激活区。②正常对照组单眼刺激分析中引起视觉皮层反应的优势大脑半球均为右侧,同一个个体的左眼、右眼的优势半球一致；③屈光参差性弱视儿童弱视眼较正常对照组在中颞区(MT区)、Brodmann17、18、19、37区激活强度均减少,但以中颞区(MT区)、Brodmann 19、37区减少显著,颞中回、枕中回、舌回为低于正常对照的主要脑区,与正常对照组相比额叶有较大范围激活；④屈光参差性弱视对侧眼较正常对照组在Brodmann37、18、19区激活强度均有所减少,但以Brodmann 37、18区减少显著,而颞中回、楔叶、舌回为低于正常对照的主要脑区；⑤两眼间比较,弱视眼较对侧眼在中颞区(MT区)和Brodmann19区、18区为主要激活体积及强度减少区,而Brodmann17区和37区未见显著性差异,颞中回、楔叶为低于对侧眼的主要脑区,额中回为弱视眼较对侧眼主要增强脑区；⑥弱视眼的视力损害程度与皮层视觉运动功能的损害程度并不同步。 [结论]1、视觉运动功能皮层主要定位于Brodmann37、39及19区交界处的中颞区(MT),同时枕叶、顶叶部分脑区亦参与视觉运动信号的反应。 2、屈光参差性弱视儿童视觉运动功能皮层BOLD-fMRI信号异常表现为脑皮层激活区体积和强度较正常儿童明显下降,非弱视眼亦存在显著性异常。 3、单眼视觉运动刺激时,弱视眼有更多的脑区参与反应。 4、视力与皮层BOLD-fMRI信号强度无相关性,与视觉运动刺激相关功能皮层BOLD-fMRI信号的产生机制仍需深入探讨。 5、水平运动光栅形成的生理刺激,除具有单纯光感觉外,还具有视觉运动的成分。fMRI能直视视觉皮质的活动情况,可用于探索弱视的病理生理基础。
[Abstract]:[Objective] To investigate the effects of visual motor function in anisometropic amblyopia and the possible relationship between cortical activation and visual impairment by using blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI).
[Methods] BOLD-fMRI technique and block design pattern were used to obtain data from 1.5T MRI scanned images. Neuropsychological programming software "Presention" was used in the stimulus program. The stimulus task was to move the vertical sinusoidal grating horizontally to the left and to the right. The spatial frequency was 5 cycle/degree (c/d), the moving speed was 4 [sec] and the contrast was 4 [sec]. Fifty percent of the patients in the anisometropic amblyopia group were selected from the ophthalmic clinic of our hospital. After removal of head movement and motion artifacts, a total of 20 patients, including 11 males and 9 females, aged 6-15 years, were removed. After head movement and motion artifacts, 23 patients, including 11 males and 12 females, aged 6-14 years, underwent mydriatic optometry and examination before the experiment. There were no other serious ocular and nervous system diseases and no history of systemic diseases in both the experimental group and the control group. BOLD data were collected by EPI (Echo Planar Imaging) sequence and 3D-FSPGR sequence. After the visual task and data acquisition, the subjects were processed and analyzed by AFNI, MATLAB and SPM5 software. The pretreatment included time correction, head movement correction, spatial standardization and three-dimensional spatial smoothing. Correlation analysis of time signal intensity curves was used to determine the activation regions directly related to the differences between stimuli and control tasks. Then t-test was performed at pixel level to screen the brain activation regions. Visual eye, contralateral eye and normal control group, left eye and right eye were analyzed, and the average activation map was obtained. 3. The activation area and activation intensity of the stimulation brain in amblyopic children with anisometropic amblyopia, contralateral eye and control group were compared. 4. The relationship between the damage of cortical neurons and visual impairment in amblyopia.
[Results] In the normal control group, the most obvious activation areas of left and right eye stimulation were middle temporal area (MT area), Brodmann 37 and 19 were middle, inferior temporal lobe and middle occipital lobe, followed by Brodmann 17, 18 were lingual gyrus, cuneiform gyrus, anterior cuneiform lobe cortex, and there were also activation areas of posterior cerebellum and parietal lobe. The dominant cerebral hemisphere of cortical response was right side, the same individual left eye, the dominant right eye hemisphere was the same; (3) The activation intensity of anisometropic amblyopia in the middle temporal area (MT area), Brodmann 17, 18, 19, 37 area decreased significantly in the middle temporal area (MT area), Brodmann 19, 37 area, middle temporal gyrus, occipital gyrus, tongue compared with the normal control group. (4) The activation intensity of the contralateral eye in anisometropic amblyopia was lower than that in the normal control group in Brodmann 37,18,19 area, but the activation intensity in Brodmann 37,18 area was significantly lower than that in the normal control group, while in the middle temporal gyrus, cuneiform lobe and lingual gyrus were lower than that in the normal control group. Compared with the contralateral eyes, the amblyopic eyes were mainly in the middle temporal area (MT area) and Brodmann 19 area, and the 18 area was the main area of reduced activation volume and intensity, while the Brodmann 17 area and 37 area had no significant difference. The degree of damage is not synchronous with the impairment of cortical visual motor function.
[Conclusion] 1. The visual motor cortex is mainly located in the middle temporal region (MT) at the junction of Brodmann 37, 39 and 19. The occipital and parietal lobes are also involved in the visual motor response.
2. The abnormal BOLD-fMRI signals in the visual motor cortex of anisometropic amblyopia children showed that the volume and intensity of cortical activation areas were significantly decreased compared with normal children, and there were also significant abnormalities in non-amblyopic eyes.
3, in monocular visual stimulation, there are more brain regions in the amblyopic eye.
4. There is no correlation between visual acuity and cortical BOLD-fMRI signal intensity. The mechanism of BOLD-fMRI signal production in cortex related to visual motor stimulation needs further study.
5. The physiological stimulus formed by horizontal motion grating has not only simple light sensation, but also visual movement component. fMRI can see the activity of visual cortex directly and can be used to explore the pathophysiological basis of amblyopia.
【学位授予单位】：天津医科大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：R777.44
本文编号：2211568
[Abstract]:[Objective] To investigate the effects of visual motor function in anisometropic amblyopia and the possible relationship between cortical activation and visual impairment by using blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI).
[Methods] BOLD-fMRI technique and block design pattern were used to obtain data from 1.5T MRI scanned images. Neuropsychological programming software "Presention" was used in the stimulus program. The stimulus task was to move the vertical sinusoidal grating horizontally to the left and to the right. The spatial frequency was 5 cycle/degree (c/d), the moving speed was 4 [sec] and the contrast was 4 [sec]. Fifty percent of the patients in the anisometropic amblyopia group were selected from the ophthalmic clinic of our hospital. After removal of head movement and motion artifacts, a total of 20 patients, including 11 males and 9 females, aged 6-15 years, were removed. After head movement and motion artifacts, 23 patients, including 11 males and 12 females, aged 6-14 years, underwent mydriatic optometry and examination before the experiment. There were no other serious ocular and nervous system diseases and no history of systemic diseases in both the experimental group and the control group. BOLD data were collected by EPI (Echo Planar Imaging) sequence and 3D-FSPGR sequence. After the visual task and data acquisition, the subjects were processed and analyzed by AFNI, MATLAB and SPM5 software. The pretreatment included time correction, head movement correction, spatial standardization and three-dimensional spatial smoothing. Correlation analysis of time signal intensity curves was used to determine the activation regions directly related to the differences between stimuli and control tasks. Then t-test was performed at pixel level to screen the brain activation regions. Visual eye, contralateral eye and normal control group, left eye and right eye were analyzed, and the average activation map was obtained. 3. The activation area and activation intensity of the stimulation brain in amblyopic children with anisometropic amblyopia, contralateral eye and control group were compared. 4. The relationship between the damage of cortical neurons and visual impairment in amblyopia.
[Results] In the normal control group, the most obvious activation areas of left and right eye stimulation were middle temporal area (MT area), Brodmann 37 and 19 were middle, inferior temporal lobe and middle occipital lobe, followed by Brodmann 17, 18 were lingual gyrus, cuneiform gyrus, anterior cuneiform lobe cortex, and there were also activation areas of posterior cerebellum and parietal lobe. The dominant cerebral hemisphere of cortical response was right side, the same individual left eye, the dominant right eye hemisphere was the same; (3) The activation intensity of anisometropic amblyopia in the middle temporal area (MT area), Brodmann 17, 18, 19, 37 area decreased significantly in the middle temporal area (MT area), Brodmann 19, 37 area, middle temporal gyrus, occipital gyrus, tongue compared with the normal control group. (4) The activation intensity of the contralateral eye in anisometropic amblyopia was lower than that in the normal control group in Brodmann 37,18,19 area, but the activation intensity in Brodmann 37,18 area was significantly lower than that in the normal control group, while in the middle temporal gyrus, cuneiform lobe and lingual gyrus were lower than that in the normal control group. Compared with the contralateral eyes, the amblyopic eyes were mainly in the middle temporal area (MT area) and Brodmann 19 area, and the 18 area was the main area of reduced activation volume and intensity, while the Brodmann 17 area and 37 area had no significant difference. The degree of damage is not synchronous with the impairment of cortical visual motor function.
[Conclusion] 1. The visual motor cortex is mainly located in the middle temporal region (MT) at the junction of Brodmann 37, 39 and 19. The occipital and parietal lobes are also involved in the visual motor response.
2. The abnormal BOLD-fMRI signals in the visual motor cortex of anisometropic amblyopia children showed that the volume and intensity of cortical activation areas were significantly decreased compared with normal children, and there were also significant abnormalities in non-amblyopic eyes.
3, in monocular visual stimulation, there are more brain regions in the amblyopic eye.
4. There is no correlation between visual acuity and cortical BOLD-fMRI signal intensity. The mechanism of BOLD-fMRI signal production in cortex related to visual motor stimulation needs further study.
5. The physiological stimulus formed by horizontal motion grating has not only simple light sensation, but also visual movement component. fMRI can see the activity of visual cortex directly and can be used to explore the pathophysiological basis of amblyopia.
【学位授予单位】：天津医科大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：R777.44
【参考文献】
相关期刊论文 前1条
1 王健;李传明;余琼武;汪辉;周杨;谢兵;邱明国;翁旭初;;屈光参差性弱视患者皮层功能损害及其与视力损害关系的功能MRI研究[J];中华放射学杂志;2006年12期
，本文编号：2211568
本文链接：https://www.wllwen.com/yixuelunwen/yank/2211568.html
最近更新
教材专著
