Sheybani Laurent, De Stefano Pia, Seeck Margitta, Vulliémoz Serge, Mégevand Pierre
Department of Clinical and Experimental Epilepsy, University College London, London, United Kingdom.
Department of Clinical Neuroscience, Geneva University Hospitals and University of Geneva, Geneva, Switzerland.
Clin Neurophysiol Pract. 2025 Sep 11;10:392-401. doi: 10.1016/j.cnp.2025.09.001. eCollection 2025.
Focal slowing in scalp electroencephalography (EEG) is classically seen as an unspecific entity in terms of its association with both epilepsy and distinct aetiologies. This could be due to a lack of standardization in the assessment of slowing morphology, in distinction to precise guidelines utilized in the evaluation of pathological activities, such as interictal epileptiform discharges (IEDs). However, consistent features can be identified, which can be informative about the underlying brain pathology and risk of seizures. In this review, we discuss the different kinds of focal slowing, focusing mainly on the delta range (0.5-4 Hz), their respective pathological processes and their prognostic value in terms of likelihood to be associated with acute seizures or epilepsy. We then present new findings on source localization of focal slowing. Last, we review recent evidence of interaction between focal slow activities and epileptic activities. Our didactic approach will guide readers through important aspects of an EEG entity that might have been neglected despite past and recent observations of its relevance in epilepsy.
头皮脑电图（EEG）中的局灶性慢波，传统上被视为一种非特异性表现，因为它与癫痫及不同病因均有关联。这可能是由于在慢波形态评估方面缺乏标准化，与评估病理性活动（如发作间期癫痫样放电，IEDs）所采用的精确指南不同。然而，可以识别出一些一致的特征，这些特征能够为潜在的脑病理学及癫痫发作风险提供信息。在本综述中，我们讨论了不同类型的局灶性慢波，主要聚焦于δ频段（0.5 - 4Hz），它们各自的病理过程以及在与急性发作或癫痫相关可能性方面的预后价值。然后，我们介绍了局灶性慢波源定位的新发现。最后，我们回顾了局灶性慢活动与癫痫活动之间相互作用的最新证据。我们的教学方法将引导读者了解脑电图这一实体的重要方面，尽管过去和近期都观察到它在癫痫中的相关性，但这些方面可能被忽视了。
