局灶性癫痫缺省模式改变的功能连接磁共振成像研究

Disturbances of default mode in focal epilepsy:a functional connectivity MRI study

目的评价局灶性癫痫患者缺省模式网络(DMN)的异常改变。方法选取33例局灶性癫痫患者的静息功能磁共振成像数据,根据致痫病灶与缺省模式脑区的关系,分为两组:位于DMN脑区的10例,位于与DMN相反的外在系统脑区23例。以癫痫灶为种子点,采用基于回归模型的功能连接算法进行全脑的相关计算,观察DMN。以一组年龄、性别配比的正常人作为对照研究。结果癫痫灶位于DMN脑区内的10例患者,其中7例癫痫灶与DMN脑区表现为相位上的负相关,1例与DMN脑区部分负相关,2例呈正相关但连接度较对照显著减低。另外一组23例患者中,18例致痫灶与DMN脑区负相关,但相比正常人连接度降低,2例正相关,3例部分负相关。结论致痫灶持续痫电发放干扰了正常的DMN,这一现象在局灶性癫痫普遍存在。

Objective To evaluate the changes of functional connectivity in the default mode network（DMN）of patients with focal epilepsy.Methods Thirty-three patients with focal epilepsy and 33 normal controls matched with gender/age were enrolled in this study.The patients were divided into two groups according to relationships between the focal location and default mode network,10 belonged to the first group that the epileptogenic focus located in the region of default mode,and 23 belonged to the second group that the epileptogenic focus located in the region of extrinsic system.Functional connectivity was calculated with the seed point of epileptogenic focus.The relationship of connectivity between the epileptogenic focus and default network was studied in comparison with the controls.Results Of the patients in the first group,7 patients showed reversed negative correlation between the focus and default mode.One patient showed negative correlation with part of default mode.Meanwhile,among the patients in the second group,18 patients showed negative correlation between focus and default mode with the lower connectivity in contrast with controls.Conclusion The default mode network is disturbed by the epileptic activity in the patient with focal epilepsy,which suggesting the changes of default mode generally exist in the focal epilepsy in addition to the generalized epilepsy.