青少年肌阵挛癫痫脑电图的多尺度特征分析

Multi-scale characteristics in EEG signal in juvenile myoclonic epilepsy

目的运用子波分析的方法研究青少年肌阵挛（juvenile myoclonic epilepsy,JME）脑电图信号的多尺度定量特征。方法对12例JME患者痫性放电的脑电图信号采用Gauss连续子波变换（Gauss continuous wavelet transform,GCWT）进行分解,观察放电过程中脑电信号时频演变过程,在此基础上进行子波功率谱分析,并将上述结果与正常对照脑电图分析结果进行对比研究。结果 JME患者痫性放电的脑电信号经GCWT,均显示0.6 Hz和4.5 Hz显著增强的节律性活动,且两个频带上的节律性活动明显相关,0.6 Hz的低频活动以正相支开始,随后出现负相支,最后以正相支结束;而正常对照在0.023~34.68 Hz均可见节律性活动。通过子波谱分析发现JME患者痫性放电在0.6 Hz和4.5 Hz出现两个窄且高的功率峰;而正常对照的脑电信号在0.05 Hz,1.35 Hz和10 Hz存在三个宽而低的功率峰。结论 JME患者痫性放电的脑电信号的多尺度特征表现为0.6 Hz和4.5 Hz显著增强的节律性活动,且这一特征可由子波功率谱分析证实。

Objective Objective To study the multi-scale characteristics of the EEG signal in juvenile myoclonic epilepsy（JME） using multi-scale wavelet transform.Methods The EEG signals with multi-scale resolution in 12 patients of JME were analyzed using Gauss Continuous Wavelet Transform（GCWT）.The time-frequency dynamics of JME discharges and their multi-scale power spectrum were included.Results There were increased rhythmic activities at 0.6 Hz and 4.5 Hz in discharges of JME and the rhythmic activities at 0.6 Hz and 4.5 Hz were correlated with each other.The low frequency activities started with a positive-phase,followed by a negative-phase and ended with a positive-phase in all discharges.Rhythmic activities from 0.023 Hz to 34.68 Hz are found in the normal controls.The JME discharges had two high power narrow peaks at frequency of 0.6 Hz and 4.5 Hz while normal subjects had three low power wide peaks at 0.05 Hz,1.35 Hz and 10 Hz.Conclusions Enhanced rhythmic activities as evidenced by the spectrum at both 0.6 Hz and 4.5 Hz are the key characteristics of EEG signals in JME discharges.