静息态功能磁共振和纤维追踪技术在单纯脊髓受累型多发性硬化患者的临床应用

目的联合应用静息态功能磁共振成像(resting-state functional magnetic resonance imaging，RS-fMRI)和纤维追踪技术探索单纯脊髓受累的多发性硬化患者(multiple sclerosis patients with simple spinal cord involvement，MS-SSCI)脑部功能和脑白质完整性是否有改变。材料与方法利用RS-fMRI比较22例MS-SSCI及22例年龄、性别相匹配的健康对照组的基础脑活动，将组间有差异的区域作为感兴趣区，利用纤维追踪技术重建穿过这些区域的白质纤维束，比较两组之间纤维束的部分各向异性(FA)和表观弥散系数(ADC)，最后将MS-SSCI组感兴趣区低频振幅(amplitude of low frequency fluctuation，ALFF)、FA、ADC分别与临床扩展残疾状态量表(expanded disability states scale，EDSS)评分进行Pearson相关分析。结果与健康对照组相比，MS-SSCI组右侧海马ALFF值明显减低，左侧额中回、左侧后扣带回、右侧枕中回ALFF值明显增高(双样本t检验，经AlphaSim校正，P＜0.01，体素大小＞40)，MS-SSCI组右侧海马FA值(t右侧海马=2.099， P右侧海马=0.042)和ADC值(t右侧海马=－2.053，P右侧海马=0.047)存在明显差异；MS-SSCI左侧后扣带回ALFF值与EDSS显著相关，结构变化参数与EDSS间无明显相关性(P＞0.05)。结论 MS-SSCI脑内存在功能和结构异常，功能改变与认知障碍密切相关。

The study of resting state functional magnetic resonance and ifber tracking in multiple sclerosis patients with simple spinal cord involvement

Objective:To explore the changes of the brain functional activity and the integrity of brain white matter in multiple sclerosis patients with simple spinal cord involvement (MS-SSCI) by using resting-state functional magnetic resonance imaging (RS-fMRI) and ifber tracking. Materials and Methods:Amplitude of low-frequency fluctuation (ALFF) was compared between 20 MS-SSCI and 20 age-and gender-matched normal controls by using RS-fMRI and the brain regions showing significant difference between groups were defined as the regions of interest (ROI). Fiber tracking was then used to reconstruct the white matter fiber within ROI and then the fractional anisotropy (FA) and the apparent diffusion coefifcient (ADC) were compared between the two groups. The relationships between ALFF, FA, ADC of ROI and the expanded disability states scale (EDSS) scores were further explored.Results:Compared with the controls, ALFF decreased in the right hippocampus, but increased in the left middle frontal lobe, left posterior cingulate gyrus and right middle occipital lobe (two-samplet test, after AlphaSim correction,P<0.01, voxel size>40), MS-SSCI showed signiifcant difference of FA (tright hippocampus=2.099,Pright hippocampus=0.042) and ADC (tright hippocampus=-2.053,Pright hippocampus=0.047)in the right hippocampus; A significant correlation between EDSS scores and ALFF was noted only in the left posterior cingulate gyrus, while no significant correlation between structural parameters and EDSS scores.Conclusion:Our results detected functional and structural abnormalities in MS-SSCI. Moreover, fluctuational abnormalities was closely related to cognitive impairment.