无灶性癫痫患者分频段低频振幅的静息态功能磁共振研究

Frequency-Dependent Alterations in the Amplitude of Low-Frequency Fluctuations in Patients with Non-Lesional Epilepsy: A Resting-State fMRI Study

目的应用静息态功能磁共振成像(rs-fMRI)低频振幅(ALFF)方法评价无灶性癫痫(NLE)患者不同频段下(slow-4:0.027～0.073 Hz;slow-5:0.01～0.027 Hz)大脑自发活动的改变。方法对42例无灶性癫痫患者和42例性别、年龄相匹配的健康志愿者进行rs-fMRI扫描并采集数据,应用DPARSF进行数据预处理。利用SPM8混合设计方差分析比较两组大脑低频振荡信号的频段效应、组间效应以及两者交互效应,并分别比较slow-4和slow-5频段下两组之间ALFF值差异。结果与健康志愿者相比,NLE患者ALFF值增高位于双侧颞中回、右侧枕中回,ALFF值减低主要位于右侧小脑后叶及部分默认模式网络脑区。与slow-5频段相比,slow-4频段ALFF值增高主要位于脑干和小脑;ALFF值减低主要位于皮层脑区。slow-4频段与slow-5频段分别检测NLE异常活动脑区的敏感性也有所差异。结论 NLE患者大脑神经元活动存在广泛异常,部分脑区的异常活动具有频率相关性,slow-4、slow-5频段能够相互补充的发现异常活动的脑区,为研究癫痫的病理生理机制提供新的视角。

Objective To evaluate the low frequency amplitude(ALFF)of resting state functional magnetic resonance imaging(rs-fMRI)in patients with non-focal epilepsy(NLE)in different frequency bands(slow-4:0.027~0.073 Hz;slow-5:0.01~0.027 Hz)of the changes in the brain’s spontaneous activity.Methods Forty-two patients with non-focal epilepsy and 42 healthy and age-matched healthy volunteers were scanned with rs-fMRI and data were collected.Data pretreatment was performed using DPARSF.The SPM8 mixed design analysis of variance was used to compare the frequency effect,inter-group effect and interaction between the two groups of low-frequency oscillation signals,and compare the difference of ALFF between the two groups in the slow-4 and slow-5 bands.Results Compared with healthy volunteers,the ALFF value of NLE patients was increased in the bilateral medial temporal and medial occipital gyrus.The ALFF value was mainly located in the right posterior cerebellum and some of the default mode network brain regions.Compared with the slow-5 band,the increase in ALFF in the slow-4 band is mainly located in the brainstem and cerebellum;the decrease in ALFF is mainly in the cortical brain region.The sensitivity of the slow-4 band and the slow-5 band to detect NLE abnormal activity brain regions were also different.Conclusion There are a wide range of abnormalities in brain neuron activity in NLE patients.The abnormal activities of some brain regions are frequency-related.The slow-4 and slow-5 bands can complement each other to find abnormal brain regions,which provides new research for the pathophysiological mechanism of epilepsy.Perspective.