复发缓解型多发性硬化的脑白质静息态fMRI研究

White Matter Resting-state fMRI Activity in Relapsing-remitting Multiple Sclerosis

目的探讨复发缓解型多发性硬化(RRMS)患者脑白质静息态功能磁共振成像(rs-fMRI)局部一致性(ReHo)及基于白质纤维束的大尺度功能连接的改变。方法28例RRMS患者和25名匹配的健康对照组志愿者(HC)纳入本研究,并搜集临床和rs-fMRI数据。结果RRMS患者胼胝体、内囊、放射冠、脑桥交叉束、扣带束及大脑脚等区域的ReHo显著减低(P<0.05,FDR校正),并且内囊后肢和放射冠区域的ReHo值与病程显著正相关,内囊前肢的ReHo值与扩展残疾状态量表(EDSS)评分显著负相关(P<0.05)。基于脑白质分割的大尺度网络连接分析发现RRMS患者纤维束间的功能连接主要是显著增加,特别是连接海马与丘脑、胼胝体与扣带、上下纵束、钩束等的功能连接增加,胼胝体小弯和右侧上纵束的功能连接显著减低(P<0.05,FDR校正)。结论RRMS患者脑白质区域的rs-fMRI信号局部活动和功能连接存在显著的组间差异,特别是涉及感觉运动及默认网络的白质连接,可能是RRMS的运动及认知损害的重要贡献和灰质"失连接"的基础,其之间的关联还需要进一步的探索研究。

Objective To investigate regional homogeneity(ReHo)and functional connectivity alterations of resting-state functional MRI(fMRI)in white matter in patients with relapsing-remitting multiple sclerosis(RRMS).Methods Twenty-eight patients with RRMS and 25 matched healthy controls were enrolled in the study,and clinical and resting-state fMRI data for each subject were collected.Results The ReHo was significantly reduced in corpus callosum,internal capsule,corona radiata,pontine crossing tract,cingulum and cerebral peduncle in the patients with RRMS(P<0.05,FDR corrected).ReHo values within the posterior limb of internal capsule and the corona radiata regions showed significantly positive correlations with disease course,respectively;and the ReHo value of the forelimb of the internal capsule was significantly negatively correlated with the EDSS score.Large-scale network analysis based on white matter parcellations suggested prominent increases in functional connectivity among the fiber tracts of patients with RRMS,especially among hippocampus,thalamus,corpus callosum,cingulum,superior and inferior longitudinal fasciculus,uncinate fasciculus,etc.Decreased functional connectivity was also found between the forceps minor and the superior longitudinal fasciculus(P<0.05,FDR corrected).Conclusion This study found that there are significant inter-group differences in the local activity and functional connectivity of resting-state fMRI signals in the white matter of RRMS patients,especially in the structural connectivity involving sensorimotor and default networks,which may be an important basis underlying"disconnectivity"in RRMS,and interpretation for motor and cognitive impairments.This relationship requires further exploration.