Stargardt病视神经小视野弥散张量成像研究

发布时间：2018-04-21 00:24

本文选题：Stargardt病 + 视神经　；参考：《郑州大学》2017年硕士论文

【摘要】：背景和目的Stargardt病(Stargardt disease,STGD)是青少年最常见的一种遗传性黄斑营养不良性眼底疾病,患者常以双眼中心视力进行性下降且不能矫正为首发症状,严重危害着青少年的视功能,全球患病率约为1/10000。STGD原发于视网膜色素上皮层,大量脂褐素沉积,感光细胞受损死亡,数目减少,最终视网膜萎缩,各层变薄。STGD具有高度的遗传异质性和复杂的临床表型。ABCA4基因为主要的致病基因,为常染色体隐性遗传。目前尚无有效的治疗方法。视网膜正中央区因含有丰富的黄色素而称为黄斑区,是视网膜上视觉最敏锐的部位。光学相干断层成像研究发现部分STGD患者视网膜神经节细胞减少及神经纤维层变薄,基于体素的形态学研究发现STGD患者视神经、视交叉、外侧膝状体、视放射及视皮层体积变小,这些研究表明STGD患者病理改变不仅局限于视网膜,整个视路尚存在病理改变。弥散张量成像(diffusion tensor imaging,DTI)能够在活体无创性定量研究脑白质纤维束的微观结构及其病理生理变化,广泛应用于视神经疾病的研究。相比于传统DTI,小视野弥散张量成像技术(reduced field of view diffusion tensor imaging,rFOV-DTI)具有提高视神经DTI图像的分辨率,减少磁敏感伪影等优势。本研究拟采用rFOV-DTI技术对STGD患者视神经进行研究,以探讨rFOV-DTI技术对STGD视神经病变的临床应用价值。材料和方法分别收集22例STGD病人(均双眼发病,44只眼)做为病变组和年龄性别与之相配的25例正常人(50只眼)做为对照组。所有研究对象均进行视力检查,并转换为最小分辨角对数表达(logarithmofminimalangleofresolution,logmar)。运用gemri7503.0t机器对所有研究对象进行磁共振数据采集,包括头颅常规mri、视神经常规mri和rfov-dti检查。运用gefunctooladw4.5工作站进行rfov-dti数据后处理得到视神经的平均扩散系数(meandiffusivity,md)图、部分各向异性(fractionalanisotropy,fa)图及本征向量图,在b0图上沿视神经前、中、后三段手动绘制3个感兴趣区(regionofinterest,roi),每个roi的面积约为6mm2,分别计算每条视神经三个感兴趣区fa值、md值、λ//值、λ⊥值的平均值。采用两独立样本t检验比较病变组与正常对照组视神经dti主要参数值之间的差异。采用配对样本t检验比较病变组左、右侧视神经dti主要参数值之间的差异。采用kruska-wallis检验方法比较对照组及不同分期病人视神经dti主要参数值之间的差异,并采用dunn-bonferroni检验方法进一步比较对照组及不同分期病人视神经dti主要参数值两两之间的差异。采用spearman秩相关分析病变组logmar与dti主要参数值之间的关系。结果1.所有研究对象常规头颅及视神经磁共振未见明显异常。2.与正常对照组相比,stgd病人视神经fa值降低、md值、λ//值及λ⊥值均升高,差异具有统计学意义(p0.05)。病变组左、右侧视神经fa值、md值、λ//值及λ⊥值之间的差异无统计学意义(p0.05)。3.对照组及病变组四个分期病人视神经fa值、md值、λ//值、λ⊥值总体分布不同,差异具有统计学意义(p0.05)。4.对照组与i期病人视神经fa值、md值、λ//值、λ⊥值总体分布间的差异无统计学意义(p0.05);ii期病人fa值低于正常对照组(p0.05);iii期、iv期病人fa值低于正常对照组和i期病人(p0.05),md值、λ//值、λ⊥值则高于正常对照组和i期病人(p0.05),其余组间差异无统计学意义。5.病变组logmar与fa值之间呈负相关(r=㧟0.641,p0.05),与md值、λ//值、λ⊥值之间呈正相关(r=0.707,p0.05;r=0.689,p0.05;r=0.668,p0.05)。结论:1.rFOV-DTI技术较常规磁共振更能敏感地发现STGD视神经病变,为STGD视神经病理改变的诊断提供影像学依据。2.rFOV-DTI参数的变化可定量评价STGD视神经纤维破坏的严重程度,且视神经rFOV-DTI参数与LogMRA之间存在相关。3.STGD I期患者视神经尚未出现病理改变,II期、III期、IV期视神经出现不同程度的病理改变。
[Abstract]:Background and objective Stargardt disease (Stargardt disease, STGD) is one of the most common genetic macular malnutrition fundus diseases in adolescents. Patients often suffer from a progressive decline in the visual acuity of the binocular center and can not be corrected as the first symptom, which seriously endangers the visual function of young people. The global prevalence rate is about 1/10000.STGD on the retinal pigment. The cortex, a large number of lipofuscin deposits, the death of the photoreceptor cells, the decrease of the number, the eventual atrophy of the retina, and the thinning of the retina, the.STGD has a high genetic heterogeneity and a complex clinical phenotype.ABCA4 based on the main pathogenic gene, which is an autosomal recessive inheritance. There is no effective therapy at present. The central retinal area is rich in the retina. Yellow pigment, called macular region, is the most perceptive part of the retina. Optical coherence tomography found that the retinal ganglion cells in some STGD patients have decreased and the nerve fiber layer thinning. The volume of optic nerve, optic chiasma, lateral geniculate body, optic and visual cortex in STGD patients are smaller, based on the morphologic study of voxel. The study shows that the pathological changes of STGD patients are not only limited to the retina, but there are still pathological changes in the whole visual pathway. Diffusion tensor imaging (DTI) can be used to study the microscopic structure and pathophysiological changes of the white matter fiber bundles in the living body, and it should be widely used in the study of optic nerve diseases. Compared with the traditional DTI, it is less than the traditional DTI. The reduced field of view diffusion tensor imaging, rFOV-DTI has the advantages of improving the resolution of the optic nerve DTI image and reducing the magnetic sensitivity artifact. This study intends to use rFOV-DTI technique to study the optic nerve of STGD patients to explore the clinical application value of rFOV-DTI technology to the optic neuropathy. Materials and methods were used to collect 22 cases of STGD (both binocular and 44 eyes) as the lesion group and 25 normal persons (50 eyes) matched with age and sex (50 eyes) as the control group. All the subjects performed the visual examination and converted to the minimum resolution angle logarithmic expression (logarithmofminimalangleofresolution, LogMAR). The gemri7503.0t machine was used. All the subjects were collected for magnetic resonance data, including routine cranial MRI, routine MRI and rfov-dti examination of optic nerve. The average diffusion coefficient of optic nerve (meandiffusivity, MD), partial anisotropy (fractionalanisotropy, FA) and eigenvector were obtained by rfov-dti data processing by gefunctooladw4.5 workstation. In B0 On the graph, 3 regions of interest (regionofinterest, ROI) were manually drawn along the front, middle, and three segments of the optic nerve. The area of each ROI was about 6mm2. The mean values of FA, MD, / / / / / / value of each optic nerve were calculated respectively. The two independent sample t test was used to compare the main parameters of the optic nerve DTI in the lesion group and the normal control group. The difference between the main parameters of the left and right optic nerve DTI in the left and right optic nerve was compared with the paired sample t test. The difference between the main parameters of the optic nerve of the optic nerve in the control group and the different staging patients was compared by the kruska-wallis test, and the dunn-bonferroni test method was used to compare the visual gods of the control group and the different staging patients. The difference between the main parameter values of DTI was 22. Spearman rank correlation was used to analyze the relationship between the LogMAR and the main parameters of the DTI. Results 1. all the subjects with the normal head and the optic nerve MRI did not see the obvious abnormal.2. as compared with the normal control group, and the FA value of the optic nerve in the STGD patients decreased, the MD value, the value of lambda / / / the value and the lambda value were all increased. The difference was statistically significant (P0.05). There was no significant difference between the left of the lesion group, the FA value of the right optic nerve, the value of MD, the value of lambda and the value of lambda value (P0.05), the FA value of the optic nerve in the.3. control group and the four staging patients of the pathological group, the MD value, and the value of [lambda] / / / / / / / / / / / / / / value, the difference was statistically significant (P0.05) the.4. control group and the FA optic FA of the I patients. Value, MD value, and / / / / / / value, there was no significant difference between the total distribution of lambda values (P0.05), and the FA value of II patients was lower than that of the normal control group (P0.05), and the FA of IV patients was lower than the normal control and I patients (P0.05), MD value, and the value of lambda was higher than that of the normal control group and the I phase, and the difference between the other groups was not statistically significant. There was a negative correlation between the value of LogMAR and FA (r=? 0.641, P0.05), which was positively correlated with the value of MD, lambda / / / / / value, and [r=0.707, P0.05; r=0.689, P0.05; r=0.668, P0.05). Conclusion: 1.rFOV-DTI technology is more sensitive than conventional magnetic resonance to detect optic neuropathy, providing imaging based parameters for the diagnosis of optic neuropathological changes The changes can be used to quantitatively evaluate the severity of STGD optic nerve fiber damage, and there is no pathological changes in the optic nerve between the rFOV-DTI parameters of the optic nerve and LogMRA in the.3.STGD I phase, and the pathological changes of the optic nerve in II, III and IV stages.

【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R445.2;R774.5

【参考文献】