Pedersen Nigel P, Raghu Ashley, Shivamurthy Veeresh Kumar N, Chern Joshua J, Gross Robert E, Willie Jon T, Dingledine Raymond J, Kheder Ammar
Department of Neurology, and UC Davis Comprehensive Epilepsy Center, University of California, Davis School of Medicine, Center for Neuroscience, Davis, CA 95618, USA.
Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA.
Brain Commun. 2024 Jul 16;6(4):fcae179. doi: 10.1093/braincomms/fcae179. eCollection 2024.
The piriform cortex is recognized as highly epileptogenic in rodents, yet its electrophysiological role in human epilepsy remains understudied. Recent surgical outcomes have suggested potential benefits in resecting the piriform cortex for cases of medial temporal lobe epilepsy. However, little is known about its electrophysiological activity in human epilepsy. This case-series study aimed to explore the electrophysiological role of the piriform cortex within the epileptogenic network among patients with suspected temporal lobe epilepsy. Participants were recruited from Emory University Hospital or Children's Healthcare of Atlanta, with non-lesional frontotemporal or temporal lobe hypotheses, undergoing stereoelectroencephalographic studies. Specifically, focus was placed on patients with one or more electrode contacts in the piriform cortex. Primary objectives included determining piriform cortex involvement within the electrophysiologically defined epileptogenic network and assessing the effects of electrical stimulation. Twenty-two patients were included in the study. Notably, only one patient exhibited piriform cortex involvement at seizure onset, associated with an olfactory aura. Two patients showed early piriform cortex involvement, while others displayed late or no involvement. Electrical stimulation of the piriform cortex induced after-discharges in three patients and replicated a habitual seizure in one. These findings present a contrast to surgical outcome studies, suggesting that the piriform cortex may not typically play a significant role in the epileptogenic network among patients with non-lesional temporal lobe epilepsy.
梨状皮层在啮齿动物中被认为具有高度致痫性，但其在人类癫痫中的电生理作用仍研究不足。近期的手术结果表明，对于内侧颞叶癫痫病例，切除梨状皮层可能有益。然而，对于其在人类癫痫中的电生理活动知之甚少。本病例系列研究旨在探讨疑似颞叶癫痫患者致痫网络中梨状皮层的电生理作用。研究对象从埃默里大学医院或亚特兰大儿童医疗保健机构招募，患有非病变性额颞叶或颞叶病变，接受立体脑电图研究。具体而言，重点关注在梨状皮层有一个或多个电极触点的患者。主要目标包括确定梨状皮层在电生理定义的致痫网络中的参与情况以及评估电刺激的效果。22名患者纳入研究。值得注意的是，只有一名患者在癫痫发作起始时出现梨状皮层参与，伴有嗅觉先兆。两名患者早期出现梨状皮层参与，而其他患者则表现为晚期参与或无参与。对梨状皮层的电刺激在三名患者中诱发了放电后效应，并在一名患者中重现了习惯性癫痫发作。这些发现与手术结果研究形成对比，表明在非病变性颞叶癫痫患者中，梨状皮层通常可能在致痫网络中不发挥重要作用。
