全面强直阵挛癫痫发作间期的静息态fMRI低频振幅研究

目的 采用静息态fMRI(rs-fMRI)低频振幅(ALFF)方法观察全面强直阵挛癫痫(GTCS)发作间期脑活动水平的改变。 方法 对36例GTCS患者(GTCS组)与36名性别、年龄相匹配的健康人(正常对照组),采用3.0T超导MR仪采集rs-fMRI数据,计算并对比GTCS组相比正常对照组ALFF改变的脑区,观察ALFF改变的脑区与患者发作频率的相关性。 结果 与正常对照组相比,GTCS患者发作间期ALFF增加区域呈对称性分布,以双侧丘脑、基底核区、岛叶、小脑及前扣带回为主(P<0.05);ALFF减低的区域主要包括双侧楔前叶、内侧前额叶及后扣带回。GTCS患者的发病频率与双侧丘脑、小脑的ALFF呈正相关(r=0.510,P=0.001),与内侧前额叶、左侧楔前叶、后扣带回及双侧部分枕叶皮层的ALFF呈负相关(r=-0.351,P=0.036)。 结论 GTCS患者发作间期丘脑皮层脑区神经自发活动异常,与GTCS患者的癫痫发作相关。ALFF有助于进一步揭示GTCS的发病机制。

Study of amplitude of low frequency fluctuation in interictal epilepsy with generalized tonic clonic seizures based on fMRI

Objective To observe the interictal alteration of the brain activity level in patients with generalized tonic clonic sizure (GTCS) using the method of amplitude of low frequency fluctuation (ALFF). Methods Thirty-six patients with GTCS were included, and the same number of age- and gender-matched healthy volunteers were set as controls. Data of resting state fMRI in all subjects were obtained on 3.0T MR scanner. ALFF of the two groups were calculated and compared. The correlation between ALFF and epilepsy frequency of GTCS was observed. Results Compared with the controls, GTCS patients presented as increased ALFF in the bilateral thalamus, basal ganglia, insular lobe, cerebellum and anterior cingulate gyrus (P<0.05), reduced ALFF primarily in the bilateral precuneus, medial prefrontal lobe and posterior cingulate gyrus. In addition, ALFF in the bilateral thalamus and bilateral cerebellum positively correlated with the epilepsy frequency of the patients (r=0.510, P=0.001), while in the medial prefrontal lobe, left precuneus, posterior cingulate gyrus and part of the bilateral occipital lobes correlated negatively with the epilepsy frequency of the patients (r=-0.351, P=0.036). Conclusion The alteration of ALFF in GTCS patients' brain indicate that the abnormal brain activity in the thalamocortical circuitry correlate with the epilepsy frequency. ALFF contributes to the understanding of the pathophysiological mechanism of GTCS.