摘要： 目的  采用静息态功能磁共振（fMRI）脑网络分析技术对儿童失神发作时静息态脑网络的改变进行观察，旨在发现癫痫发作时患儿认知功能受损情况。方法  根据病例选择标准，共纳入12 例诊断明确的失神发作患儿，采用同步脑电图-fMRI 技术采集17 对弥漫性棘慢波综合发放和无发放状态下fMRI 数据；以独立成分分析法分别观察丘脑、默认网络、背侧注意网络、中央执行网络和感知觉网络等7 个静息态脑网络在不同状态下的表现情况。结果  配对t 检验及相关分析结果提示，在弥漫性棘慢波综合发放状态下丘脑表现为脑电活动同步性增强，且其强度与弥漫性棘慢波综合发放持续时间呈正相关（r = 0.890，P = 0.000）；默认网络（r = -0.706，P = 0.000）、背侧注意网络（r = - 0.829，P = 0.000）、中央执行网络（r = - 0.905，P = 0.000）等负责高级认知功能处理的静息态脑网络则表现为脑电活动同步性降低，并与弥漫性棘慢波综合发放持续时间呈负相关。而低级的感知觉网络的改变与弥漫性棘慢波综合发放无显著相关关系（P > 0.05）。结论  本研究首次验证丘脑可能与儿童期失神癫痫弥漫性棘慢波综合发放有关，并首次提出，除默认网络功能外，儿童失神发作还可表现为注意力及执行控制能力等高级认知功能受损，而低级感知觉功能虽可能受累但不明显。这一发现有益于对儿童失神发作时意识受损的病理生理学机制的理解。

关键词: 癫痫, 失神性； 脑电描记术； 磁共振成像； 儿童

Abstract: Objective To observe the alterations of resting-state brain functional networks in childhood absence epilepsy (CAE) using resting-state functional magnetic resonance imaging (fMRI) analysis, and to explore the cognitive disorders of children in epileptic seizures. Methods According to case selection criteria, 12 children with absence seizure were selected, from whom 17 fMRI data with generalized slow-wave discharges (GSWD) and the matched data without discharges were collected by using electroencephalogram (EEG)-fMRI synchronization. Independent component analysis was used to investigate the alterations in different states of 7 resting-state networks including the thalamus, default-mode network, dorsal attention network, central execution network and perceptive networks. Results Paired t-test and correlation analysis were used for statistical analysis. The thalamus showed increased coherence of brain activity in GSWD state, and the increased coherence was positively correlated with the durations of GSWD (r = 0.890, P = 0.000). The default-mode network (r = - 0.706, P = 0.000), dorsal attention network (r = - 0.829, P = 0.000) and central execution network (r = - 0.905, P = 0.000), which dealt with high -grade cognitive functions, showed decreased coherence, and the brain activity coherence in these networks were negatively correlated with GSWD durations. However, none of low-grade perceptive networks was found to have significant alteration in GSWD state. Conclusion The increased coherence of brain activity in the thalamus may be associated with the generation of GSWD in childhood absence epilepsy. Besides the default brain function, the processes of attention and cognitive execution may also be impaired in childhood absence epilepsy, while low-grade perceptive functions may not be greatly impacted. This study may contribute to the understanding of pathophysiological mechanism of impaired consciousness in childhood absence epilepsy.

Key words: Epilepsy, absence, Electroencephalography, Magnetic resonance imaging, Child