低频振幅分析的功能磁共振成像对额叶癫痫的研究

Application of fMRI with Amplitude of Low Frequency Fluctuation in Frontal Lobe Epilepsy

目的研究额叶癫痫(FLE)异常脑功能活动改变的分布模式,并探讨其在FLE中的病理生理机制。方法采用低频振幅(ALFF)分析的功能磁共振成像(fMRI)技术,对46例常规结构MRI阴性FLE患者及性别年龄无差异的正常对照组进行研究。通过两样本t检验,观察FLE患者相对正常对照组ALFF活动的改变情况。并采用基于体素的相关算法观察FLE患者ALFF改变与癫痫病程的关系。结果相比正常对照组,FLE患者ALFF的增高位于双内侧额叶及前扣带回、岛叶、丘脑及双侧基底节区(壳核为主),ALFF的降低位于双侧颞下回、左侧眶部额下回及顶上回。相关性分析发现,在FLE患者,与病程正相关的区域也位于内侧前额叶、双侧壳核与岛叶。结论FLE患者表现为内侧额叶、岛叶、丘脑及基底节区区域功能活动的异常,提示这些部位在FLE病理生理机制起着重要作用;并且基于ALFF分析的静息态fMRI为结构MRI阴性的FLE研究提供了可靠的工具。

Objective To study the change of brain activity in frontal lobe epilepsy, and explore its pathological physi ological mechanism in frontal lobe epilepsy. Methods 46 cases of structural MRI negative frontal lobe epilepsy （FLE） with 46 normal controls were studied using amplitude of low frequency fluctuation （ALFF） analysis of resting state function al magnetic resonance imaging （firm）. The difference of ALFF between FLE patients and controls were analysed with 2 sample test. Then the correlation between ALFF and epilepsy duration of FLE by voxel based algorithm were investigated. Results Compared with the controls, FLE patients were presented increased ALFF in bilateral mesial frontal lobe, insula, thalamus and basic ganglia, while decreased ALFF in both inferior temporal gyrus. Correlation analysis showed that ALFF in bilateral mesial frontal lobe,insula, and basic ganglia positively correlated with epilepsy duration. Conclusion The ab normal function of mesial frontal lobe, insula, thalamus and basic ganglia exist in FLE patients, which indicates these re gions play important roles in frontal lobe epilepsy pathophysiological mechanism, and amplitude of low frequency fluctuation （ALFF） analysis of resting state functional magnetic resonance imaging provides a reliable tool for structural MRI negative frontal lobe epilepsy.