Department of Neurosurgery, Epilepsy Center, Juntendo University, Tokyo, Japan.
Department of Electronic and Information Engineering, Tokyo University of Agriculture and Technology, Tokyo, Japan.
Clin Neurophysiol. 2023 Apr;148:44-51. doi: 10.1016/j.clinph.2023.01.014. Epub 2023 Feb 6.
To analyze chronological changes in phase-amplitude coupling (PAC) and verify whether PAC analysis can diagnose epileptogenic zones during seizures.
We analyzed 30 seizures in 10 patients with mesial temporal lobe epilepsy who had ictal discharges with preictal spiking followed by low-voltage fast activity patterns on intracranial electroencephalography. We used the amplitude of two high-frequency bands (ripples: 80-200 Hz, fast ripples: 200-300 Hz) and the phase of three slow wave bands (0.5-1 Hz, 3-4 Hz, and 4-8 Hz) for modulation index (MI) calculation from 2 minutes before seizure onset to seizure termination. We evaluated the accuracy of epileptogenic zone detection by MI, in which a combination of MI was better for diagnosis and analyzed patterns of chronological changes in MI during seizures.
MI and MI in the hippocampus were significantly higher than those in the peripheral regions from seizure onset. Corresponding to the phase on intracranial electroencephalography, MI decreased once and subsequently increased again. MI showed continuously high values.
Continuous measurement of MI and MI could help identify epileptogenic zones.
PAC analysis of ictal epileptic discharges can help epileptogenic zone identification.
分析相位振幅耦合（PAC）的时变特征，验证 PAC 分析是否能在发作期诊断致痫区。
我们分析了 10 例内侧颞叶癫痫患者的 30 次发作，这些患者的颅内脑电图显示发作前尖波后有发作期放电，并伴有低电压快活动模式。我们使用两个高频带（棘波：80-200 Hz，快棘波：200-300 Hz）的振幅和三个慢波带（0.5-1 Hz、3-4 Hz 和 4-8 Hz）的相位来计算调制指数（MI），从发作前 2 分钟到发作终止。我们评估了 MI 对致痫区检测的准确性，其中 MI 的组合更有利于诊断，并分析了发作期间 MI 的时变模式。
从发作开始，MI 和海马区的 MI 明显高于周围区域。与颅内脑电图的相位相对应，MI 先降低后再次升高。MI 表现出持续的高值。
连续测量 MI 和 MI 有助于识别致痫区。
发作期癫痫放电的 PAC 分析有助于识别致痫区。
