基于脑缺省模式连通性的功能磁共振成像技术对癫痫灶定位的研究

摘要

Objective Using the functional connectivity analysis based on the underlying neurophysiological characteristic that epileptic discharges can induce change of brain default mode,to develop a technique for epileptogenic localization using functional MRI(fMRI)without simultaneous electroencephalography(EEG).MethodsA data-driven method that jointly employed independent component analysis and functional connectivity analysis was used for the resting functional MRI data analysis of 12 focal epileptic patients.The independent components were ranged according to the coefficients of the negative correlation between independent component time course and the signal temporal course in the region of posterior cingulate cortex.The results were comparatively studied with simultaneous EEG-fMRI.Results In the 10 successful results from 12 patients underwent EEG-fMRI examination,the outcomes of eight subjects were concordant with pathological foci.While the results of all 10 patients processed by data-driven method were concordant with pathological foci,besides the other patients who failed to perform EEG-fRMI examination.Meanwhile,the default mode was well mapped in all patients.Conclusions The default mode-based functional connectivity analysis can localize the epileptogenic foci effectively without simultaneous EEG,besides to detect the default mode of epileptic patients.%目的 利用癫痫活动引起脑缺省模式改变的特征,采用数据驱动方式的功能连通磁共振脑数据分析方法,实现无同步脑电的癫痫灶定位技术.方法 采用组合功能连接及独立成分分析的脑连通性数据分析方法,对12例局灶性癫痫患者静息功能磁共振数据进行分析,以缺省模式区的扣带回后部为种子点,并采用其时间序列的负相关对独立成分进行排序,达到癫痫灶定位.其结果与同步联合脑电功能磁共振成像癫痫灶定位进行对比.结果 在12例局灶性癫痫同步脑电数据中有10例有效,其中8例结果与病理灶一致;而独立成分分析结果10例均与病理灶一致,并可对2例同步脑电失败的数据进行成功定位;均可发现典型的脑缺省模式网络.结论 基于脑缺省模式连通性的功能磁共振成像技术在对癫痫脑缺省模式观察的基础上,可有效地实现无同步脑电的功能磁共振成像癫痫灶定位.