Luan Cindy, Miller Jacob, Sollars Caleb, Peng Juan, Singh Jaysingh
Neurology, The Ohio State University Wexner Medical Center, Columbus, USA.
Biomedical Engineering, The Ohio State University College of Medicine, Columbus, USA.
Cureus. 2023 Jul 3;15(7):e41337. doi: 10.7759/cureus.41337. eCollection 2023 Jul.
Background Patients with drug-resistant epilepsy commonly undergo stereo-electroencephalography (SEEG) intracranial monitoring for surgical evaluation. Our current practice of defining the epileptogenic zone relies heavily on recognizing the seizure onset zone (SOZ), but the clinical significance of interictal epileptiform discharges (IEDs) is not well established. Methodology We retrospectively identified adult patients who underwent SEEG between January 2019 and May 2022. To study IED activation patterns, we classified IEDs as leading spikes (involved within the SOZ) and distant spikes (outside the SOZ). We calculated each patient's total number of brain subregions generating distant spikes. We correlated them with epilepsy type, duration, and surgical outcome (Engel I: good outcome and Engel II-IV: poor outcome). Results A total of 22 patients were identified during the study period, and 16 underwent surgical intervention (ablation or resection) with one-year post-surgery follow-up. The most common IED morphology was a single spike or sharp followed by periodic spikes or sharps. We found that 87% (n = 19/22) of leading spikes were activated during the first 24 hours of SEEG monitoring, whereas no activation pattern was observed for distant spikes. We found that a higher number of subregions generating distant spikes were associated with poor surgical outcomes (p = 0.002). However, we did not find any significant association between the number of subregions generating distant spikes with epilepsy duration (p = 0.67), temporal or extratemporal-onset epilepsy (p = 0.58), or the presence of an MRI lesion (p = 0.62). Conclusions IEDs involved within the SOZ were found to be activated during the first 24 hours of SEEG monitoring, which could aid in recognizing the pathological spikes and targeted mapping of the irritative zone. We also observed that a higher number of brain subregions generating IEDs outside the SOZ were associated with poor surgical outcomes, but this observation needs to be further studied with larger sample size prospective studies.
耐药性癫痫患者通常接受立体定向脑电图（SEEG）颅内监测以进行手术评估。我们目前定义致痫区的做法在很大程度上依赖于识别癫痫发作起始区（SOZ），但发作间期癫痫样放电（IEDs）的临床意义尚未明确。
我们回顾性地确定了2019年1月至2022年5月期间接受SEEG检查的成年患者。为了研究IEDs的激活模式，我们将IEDs分为领先棘波（涉及SOZ内）和远处棘波（SOZ外）。我们计算了每位患者产生远处棘波的脑亚区总数。我们将它们与癫痫类型、病程和手术结果（Engel I：良好结果；Engel II-IV：不良结果）进行关联。
在研究期间共确定了22例患者，其中16例接受了手术干预（消融或切除），并进行了术后一年的随访。最常见的IED形态是单个棘波或锐波，其次是周期性棘波或锐波。我们发现87%（n = 19/22）的领先棘波在SEEG监测的前24小时内被激活，而远处棘波未观察到激活模式。我们发现产生远处棘波的亚区数量较多与手术结果不良相关（p = 0.002）。然而，我们未发现产生远处棘波的亚区数量与癫痫病程（p = 0.67）、颞叶或颞叶外起始癫痫（p = 0.58）或MRI病变的存在（p = 0.62）之间存在任何显著关联。
发现在SEEG监测的前24小时内，SOZ内的IEDs被激活，这有助于识别病理性棘波和刺激区的靶向定位。我们还观察到，在SOZ外产生IEDs的脑亚区数量较多与手术结果不良相关，但这一观察结果需要通过更大样本量的前瞻性研究进一步探讨。
