复发缓解型多发性硬化联络纤维的DTI多参数定量分析

Quantitative Diffusion Tensor Imaging of Association Fibers in RRMS

目的应用扩散张量成像(DTI)检测复发缓解型多发性硬化(RRMS)联络纤维的微观结构改变,探讨DTI各种定量参数与临床功能之间的相关性。方法搜集RRMS患者33例以及年龄和性别相匹配的健康自愿者33名(对照组),均行MRI扫描,获取DTI图像,基于白质分区图谱对其进行测量分析,比较组间联络纤维主要纤维束的部分各向异性(FA)、平均扩散率(MD)、径向扩散率(RD)、轴向扩散率(AD)差异,并对RRMS患者各DTI参数与扩展残疾量表(EDSS)得分之间的相关性进行分析。结果 RRMS组较对照组在双侧扣带束、下额枕束、上额枕束、下纵束、上纵束、钩束的FA值下降,差异均具有显著性;RRMS组较对照组在双侧扣带束、下额枕束、上额枕束、下纵束、上纵束、钩束的MD值升高,差异均具有显著性;RRMS组较对照组在双侧上额枕束、双侧下纵束、双侧上纵束、右侧钩束RD值升高,差异均具有显著性;RRMS组较对照组在双侧扣带束、左侧钩束的RD值无显著差异;RRMS组较对照组双侧扣带束、下额枕束、上额枕束、下纵束、上纵束、钩束的AD值升高,差异均具有显著性。RRMS患者的双侧扣带束、下额枕束、上额枕束、下纵束、上纵束、钩束的FA值、MD值、RD值、AD值与EDSS评分之间均无相关性。结论 RRMS患者联络纤维各主要纤维束存在髓鞘完整性破坏及轴索的损害等微观结构改变;各种参数值的改变与临床功能无相关性。

Objective To detect microstructure changes of association fibers in relapsing remitting multiple sclerosis（RRMS） patients by quantitative diffusion tensor imaging（DTI）,and to explore the correlation between quantitative parameters of DTI and clinical functions. Methods Thirty three RRMS patients and thirty three healthy volunteers with matched gender/age selected as controls underwent magnetic resonance imaging（MRI） including DTI scans. According to the white matter partitioning map,fractional anisotropy（FA）/mean diffusivity（MD）/radial diffusivity（RD）/axial diffusivity（AD） of the major fiber bundle in association fibers were measured. The correlation between DTI parameters and expanded disability status scale（EDSS） scores were evaluated. Results Compared with controls,RRMS patients had lower FA value,higher MD and higher AD value in cingulum,inferior fronto-occipital fasciculus,superior fronto-occipital fasciculus,inferior longitudinal fasciculus,superior longitudinal fasciculus and uncinate fasciculus. Compared with controls,RRMS patients had higher RD value in inferior fronto-occipital fasciculus,superior fronto-occipital fasciculus,inferior longitudinal fasciculus,superior longitudinal fasciculus and right uncinate fasciculus. RD values in cingulum and left uncinate fasciculus did not show any significant differences between the two groups. In addition,EDSS scores of RRMS patients did not correlate with FA/MD/RD/AD values of the major fiber bundle in association fibers,including cingulum,inferior fronto-occipital fasciculus,superior fronto-occipital fasciculus,inferior longitudinal fasciculus,superior longitudinal fasciculus,uncinate fasciculus. Conclusion There were microstructure changes in the major fiber bundle in association fibers in the RRMS patients,such as the destruction of myelin integrity and the axonal damage. The change of the various parameters has no correlation with clinical function.