Department of Neuropediatrics, University of Freiburg, Mathildenstrasse 1, 79106 Freiburg, Germany.
Clin Neurophysiol. 2011 Jan;122(1):32-42. doi: 10.1016/j.clinph.2010.05.033. Epub 2010 Jul 6.
High-frequency (HF) changes were analysed in relation to anatomical origin of spikes, shape and occurrence within the seizure onset zone (SOZ). We evaluated whether HF changes are linked to the SOZ, as established for distinct high-frequency oscillations.
SEEG was filtered at 500 Hz and sampled at 2000 Hz. Spikes were selected by shape (spike/spike-slow wave) and location (SOZ/non-SOZ and neocortex/amygdala/hippocampus) in 15 patients. About 50 spikes were averaged for each set. Changes compared to baseline were quantified with false discovery rate controlled t-statistics using time-frequency spectra. Counts of increased or decreased time-frequency values were compared across spike categories in the 80-250 and 250-500 Hz bands.
Seventy-seven spike types were analysed. Differences between spike categories were most prominent between 250 and 500 Hz. HF changes were more frequent and larger in mesial temporal than in neocortical spikes and for spikes with slow waves than spikes alone. HF changes above 250 Hz were more frequent in spikes within than outside the SOZ.
HF increases above 250 Hz show regional differences and are very prominent in the SOZ. Hippocampal spikes have the strongest HF components.
Analysis of HF changes during spikes may provide information on differing pathophysiological mechanisms of spikes and on epileptogenicity of the tissue.
分析高频（HF）变化与棘波的解剖起源、形状以及在起始放电区（SOZ）内的发生之间的关系。我们评估了 HF 变化是否与 SOZ 有关，就像为特定高频振荡建立的那样。
对 15 名患者的 SEES 进行 500 Hz 滤波和 2000 Hz 采样。通过形状（棘波/棘慢波）和位置（SOZ/非 SOZ、新皮质/杏仁核/海马）选择棘波。对于每个设置，平均约 50 个棘波。使用时频谱的假发现率控制 t 统计量来量化与基线相比的变化。在 80-250 和 250-500 Hz 频段中，比较不同棘波类别的增加或减少的时频值计数。
分析了 77 种棘波类型。棘波类别的差异在 250-500 Hz 之间最为明显。与新皮质棘波相比，内侧颞叶棘波的 HF 变化更频繁且更大，与单纯棘波相比，棘慢波棘波的 HF 变化更频繁且更大。SOZ 内的棘波比 SOZ 外的棘波具有更高的 250 Hz 以上的 HF 变化。
高于 250 Hz 的 HF 增加显示出区域差异，在 SOZ 中非常明显。海马棘波具有最强的 HF 成分。
分析棘波期间的 HF 变化可以提供关于棘波不同病理生理机制和组织致痫性的信息。
