Rotondi Fabio, Franceschetti Silvana, Avanzini Giuliano, Panzica Ferruccio
Department of Neurophysiology, Epilepsy Centre, C. Besta Neurological Institute IRCCS Foundation, Milan, Italy; Department of Informatics, Bioengineering, Robotics and System Engineering (DIBRIS), University of Genova, Genova, Italy.
Department of Neurophysiology, Epilepsy Centre, C. Besta Neurological Institute IRCCS Foundation, Milan, Italy.
Clin Neurophysiol. 2016 Feb;127(2):1130-1137. doi: 10.1016/j.clinph.2015.09.003. Epub 2015 Sep 25.
We investigated interictal EEG activity in patients with childhood absence seizures with the aim of detecting markers of network defects generating "idiopathic" hyperexcitability in this form of epilepsy.
We included 11 drug-naïve patients with childhood absence epilepsy (CAE), and 11 age matched controls (CTRL). We analyzed interictal EEG using partial directed coherence (PDC), a connectivity estimator in frequency domain based on autoregressive multivariate (MVAR) modeling giving the advantage of indicating the direction and strength of the interactions between multiple variables.
Our results revealed the presence of an abnormal cortico-cortical network occurring in the interictal condition in CAE and involving a large span of frequencies, with prominence in the alpha band; the most evident finding was a highly significant increase of out-going connectivity involving frontal and central cortical areas in CAE patients compared to CTRL subjects.
Our observation indicates that, in interictal conditions, a distorted network characterizes CAE, and a hyperconnected network is already detectable under resting conditions in the delta, theta and alpha bands.
The increased interictal EEG connectivity demonstrated here provides support for a persistent abnormal relationship between the thalamus and a hyperexcitable cortex outside the ictal phase.
我们研究了儿童失神癫痫患者的发作间期脑电图活动，旨在检测在这种癫痫形式中产生“特发性”过度兴奋的网络缺陷标志物。
我们纳入了11例未经药物治疗的儿童失神癫痫（CAE）患者和11例年龄匹配的对照组（CTRL）。我们使用偏相干分析（PDC）来分析发作间期脑电图，PDC是一种基于自回归多元（MVAR）模型的频域连接性估计方法，具有指示多个变量之间相互作用的方向和强度的优势。
我们的结果显示，CAE患者在发作间期存在异常的皮质-皮质网络，涉及大范围的频率，在α波段尤为突出；最明显的发现是，与对照组相比，CAE患者涉及额叶和中央皮质区域的传出连接性显著增加。
我们的观察表明，在发作间期，CAE的特征是网络扭曲，并且在静息状态下，在δ、θ和α波段已经可以检测到超连接网络。
此处显示的发作间期脑电图连接性增加为发作期外丘脑与过度兴奋皮质之间持续存在的异常关系提供了支持。
