目的:应用静息态功能磁共振成像( rs-fMRI )基于体素-镜像同伦连接( VMHC )方法,分析肌萎缩侧索硬化症( ALS)患者左右脑之间的同伦功能连接改变,及其与胼胝体微结构、临床参数之间的相关性。方法选取ALS患者( ALS组)和健康志愿者(对照组)各20例,使用3.0 T MR分别采集rs-fMRI 及DTI数据。使用rs-fMRI数据处理助手( DPARSF)基于Matlab2009a平台进行数据预处理,然后采用rs-fMRI数据分析工具包( REST )中VMHC方法分析数据,比较并计算出2组VMHC相关系数改变的脑区。以VMHC差异脑区作为种子点,提取平均时间序列后进行全脑功能连接并比较2组间差异。最后采用Pearson相关分析ALS组差异脑区VMHC值和胼胝体各向异性分数( FA)值、临床参数如肌萎缩侧索硬化功能等级量表( ALSFRS-r)、病程、疾病预后比值的相关性。结果与对照组比较,ALS组中央前回、中央后回、顶下小叶、楔状叶/楔前叶和前扣带回存在VMHC显著下降[P<0.05,错误发现率(FDR)校正],辅助运动区、额上回和枕中回存在VMHC显著升高(P<0.05, FDR校正)。以VMHC改变脑区为种子点进一步的功能连接分析,证实患者组存在双侧运动区、额、颞、枕叶等多个区域功能连接下降和功能连接增强改变( P<0.05,AlphaSim 校正,簇≥228体素)。ALS患者双侧扣带前回VMHC值(0.767±0.043)和胼胝体Ⅰ区FA值(0.360±0.105)、中央前回VMHC值(0.311±0.108)和胼胝体Ⅲ区的 FA值(0.394±0.016)分别呈正相关(r =0.513, P =0.021;r=0.530, P=0.016);双侧中央前回VMHC值(0.311±0.108)和ALSFRS-r值(35.4±2.5)之间呈正相关( r=0.447, P=0.048)。其他存在显著改变的VMHC区域相关系数值与胼胝体FA值、ALSFRS-r、病程及疾病预后比值之间无相关性( P值均>0.05)。结论 ALS患者存在感觉运动区、默认网络区、额上?
Objective To investigate the difference of cerebral inter-hemispheric functional connectivity between the patients with amyotrophic lateral sclerosis ( ALS) and healthy controls ( HC) by a newly developed voxel-mirrored homotopic connectivity ( VMHC) method based on resting-state functional MRI ( rs-fMRI) , as well as its correlation to the structural imaging indices and clinical neurological scales .Methods Twenty patients with ALS ( ALS group ) and 20 age-, and sex-matched healthy controls ( HC group) were examined by rs-fMRI and diffusion tensor imaging ( DTI ) on 3.0 T MR imaging system ( Siemens Trio Tim ).The rs-fMRI data preprocessing were performed using data processing assistant for rs-fMRI ( DPARSF) based on Matlab 2009a, and the rs-fMRI data analysis toolkit ( REST) with an automated VMHC approach was utilized to calculate and compare the VMHC correlation coefficients between the ALS group and the HC group[P〈0.05, corrected with false discovery rate (FDR)].Region of interest (ROIs) were prescribed on the regions which showed abnormal VMHC coefficients in ALS group , then the mean time series of the ROIs were extracted to examine the difference of the seed ( ROIs)-based functional connectivity between the ALS and HC groups.At last, linear correlations were performed to assess the relationships among the VMHC coefficients and clinical measures including the revised amyotrophic lateral sclerosis functional rating scale ( ALSFRS-r) score, disease duration , the rate of disease progression and fractional anisotropy ( FA) values of the corpus callosum ( CC).Results Compared with HC group , the patients with ALS showed lower VMHC coefficients in the precentral gyrus ( M1 ) , postcentral gyrus ( PCG ) , inferior parietal lobule (IPL), cuneus/precuneus (Cu/Pcu), and anterior cingulate gyrus (ACC).Higher VMHC coefficients were found in the supplementary motor area , superior frontal gyrus , and middle occipital gyrus