迷走神经刺激对难治性癫痫脑功能连接的即时效应

Immediate effects of vagal nerve stimulation in brain functional connectivity in refractory epilepsy

目的:研究迷走神经刺激(vagal nerve stimulation,VNS)对药物难治性癫痫(drug⁃resistant epilepsy,DRE)患者脑功能连接的即时效应,探讨VNS抑制癫痫发作的作用机制。方法:采集14例正常被试静息态和14例DRE患者静息态和刺激态的脑磁图数据,分6个频段分析即时VNS引起的DRE患者脑功能连接的改变。结果:在静息态,DRE患者相对正常被试,功能连接显著增强。当VNS发生时,DRE患者有显著降低的功能连接,包括theta频段的左侧额中回⁃右侧嗅皮质和左侧丘脑⁃右侧距状裂周围皮层,alpha频段的左侧丘脑⁃左侧颞极颞中回之间的连接。结论:即时VNS可以降低DRE患者脑功能连接,即降低患者脑网络对发作的易损性,这可能是VNS调节DRE患者神经系统抑制癫痫发作的重要机制。

Objective:To investigate the immediate effects of vagal nerve stimulation(VNS)on the brain functional connectivity of patients with drug⁃resistant epilepsy(DRE)and explore the mechanism by whichVNS inhibits epileptic seizures.Methods:Magnetoencephalography(MEG)data were collected from 14 healthy subjects in a resting state and from 14 DRE patients in both resting and stimulated states.The changes in brain functional connectivity induced by immediate VNS were analyzed in six frequency bands.Results:In the resting state,DRE patients showed significantly enhanced functional connectivity compared to healthy subjects.When VNS occurred,DRE patients exhibited significantly reduced functional connectivity,including the connections between the left middle frontal gyrus and the right olfactory cortex and the connections between the left thalamus and the surrounding cortex of the right calcarine fissure in the theta frequency band,and the connections between the left thalamus and the left temporal polar middle temporal gyrus in the alpha frequency band.Conclusion:Immediate VNS can reduce the brain functional connectivity of DRE patients,thereby reducing the vulnerability of the brain network to seizures.This might be an important mechanism by which VNS modulates the inhibition of epileptic seizures in DRE patients.