Jabran Younes, Mahmoudzadeh Mahdi, Martinez Nicolas, Heberlé Claire, Wallois Fabrice, Bourel-Ponchel Emilie
INSERM UMR 1105, Research Group on Multimodal Analysis of Brain Function, University of Picardie Jules Verne, Amiens, France.
INSERM UMR 1105, Pediatric Neurophysiology Unit, Amiens University Hospital, Amiens, France.
Front Neurol. 2020 Sep 8;11:941. doi: 10.3389/fneur.2020.00941. eCollection 2020.
Characterization of the spatial and temporal dynamics of interictal epileptic discharges (IED) using time-frequency analysis (TFA) and electrical-source localization (ESL). TFA was performed on IED (spikes, spike waves, and polyspike waves) recorded by high-density-EEG (HD-EEG) in 19 refractory focal epileptic children. Temporal modulations related to IEDs were analyzed in a time window around the IED peaks [-1,000 to 1,000 ms]. Spatial modulations were analyzed by ESL in the time-frequency and time domains. IED were associated with complex power spectral modulations. We observed increases in power spectrum (IPS) patterns specific to IED type. For spikes, the TFA pattern consisted of an IPS (-100 to +100 ms, 4-50 Hz). For spike waves, the IPS was followed by a second IPS (+100 to +400 ms, 4-10 Hz), corresponding to the slow wave. IPS patterns were preceded (-400 to -100 ms, 4-40 Hz), and followed (+100 to +400 ms) by a decrease in the power spectrum (DPS) ( = 8). For 14 out of 19 patients, at least one ESL method was concordant with the epileptogenic area. For the remaining five patients, all of them had temporal epilepsies. ESL in the time-frequency domain (DPS/IPS) provided concordant ( = 6) or complementary ( = 4) information to the ESL in the time domain concerning the epileptogenic zone. ESL in time-frequency domain (DPS/IPS) was the only method to provide concordant information concerning the epileptogenic zone in three patients. TFA demonstrates complex time-frequency modulations of the neuronal networks around IED, suggesting that the pathological mechanisms are initiated well before onset of the classical hyper-synchronization of the IED. Combining time and time-frequency analysis of the ESL provides complementary information to define the epileptogenic zone in refractory focal epilepsy.
使用时频分析（TFA）和电源定位（ESL）对发作间期癫痫放电（IED）的时空动态进行特征描述。对19例难治性局灶性癫痫儿童的高密度脑电图（HD - EEG）记录的IED（棘波、棘慢波和多棘波）进行TFA。在IED峰值周围的时间窗口[-1000至1000毫秒]内分析与IED相关的时间调制。通过ESL在时频域和时域分析空间调制。IED与复杂的功率谱调制相关。我们观察到特定于IED类型的功率谱增加（IPS）模式。对于棘波，TFA模式由一个IPS（-100至+100毫秒，4 - 50赫兹）组成。对于棘慢波，IPS之后是第二个IPS（+100至+400毫秒，4 - 10赫兹），对应于慢波。IPS模式之前（-400至-100毫秒，4 - 40赫兹）和之后（+100至+400毫秒）有功率谱降低（DPS）（= 8）。19例患者中有14例，至少一种ESL方法与致痫区一致。其余5例患者均为颞叶癫痫。时频域（DPS/IPS）的ESL在致痫区方面为时域的ESL提供了一致（= 6）或互补（= 4）的信息。时频域（DPS/IPS）的ESL是在3例患者中提供关于致痫区一致信息的唯一方法。TFA显示了IED周围神经网络复杂的时频调制，表明病理机制在IED经典的超同步发作之前就已启动。结合ESL的时域和时频分析为定义难治性局灶性癫痫的致痫区提供了互补信息。
