脊髓型多发性硬化患者默认网络及突显网络的功能连接

Functional connectivity of default mode network and salience network in spinal form of multiple sclerosis

目的采用独立成分分析(ICA)方法分析脊髓型多发性硬化(SMS)患者脑静息态默认网络(DMN)及突显网络(SN)功能连接(FC)的异常。方法对我院22例SMS患者(SMS组)及22名健康对照者(正常对照组)行静息态fMRI,对所得数据进行ICA分析,并利用SPM8比较两组脑网络FC的差异,同时分析差异脑区的时间序列信号(FC分数)与临床扩展残疾状态量表(EDSS)评分及病程的相关性。结果与正常对照组相比,SMS组DMN的FC减弱的脑区包括双侧内侧额上回、边缘叶及双侧楔叶,FC增强的脑区包括双侧前扣带回、右侧距状皮层;SMS组SN的FC减弱的脑区为双侧内侧扣带回,FC增强的脑区延伸到双侧中央前回、左侧中央后回。两组FC分数与EDSS评分及病程均无相关性(P均>0.05)。结论 SMS患者静息态DMN、SN均存在FC异常,可能与继发于脊髓病变的逆行性神经元变性或功能网络重构有关。

Objective To evaluate the difference of brain default mode network （DMN） and salience network （SN） functional connectivity （FC） of spinal form of multiple sclerosis （SMS） by using independent component analysis （ICA）. Methods Twenty-two patients with SMS （SMS group） and 22 healthy controls （control group） underwent rest-state fMRI. The fMRI data were analyzed by ICA, and the differences of FC between the two groups were compared with SPM8. The correlation between FC of brain areas which had statistical differences and expanded disability status scale （EDSS） scores, disease duration were analyzed. Results Compared with the control group, the FC of DMN in SMS group significantly decreased in bilateral superior medial frontal gyrus, limbic lobe and bilateral cuneus, while increased in bilateral anterior cingulate cortex and right calcarine cortex; the FC of SN decreased in bilateral medial cingulate cortex, while increased in bilateral precentral gyrus, left postcentral gyrus. There were no correlation between FC and EDSS, disease duration （both P〉0.05）. Conclusion The FC abnormalities in DMN and SN may provide a valuable method to evaluate neurophysiological changes, which is probably caused by a retrograde degeneration of neurons secondary to spinal cord damage or functional network reconsitution.