Epilepsy Center, University Medical Center, Freiburg, Germany.
MediClub Georgia, Tbilisi, Georgia.
Ann Neurol. 2018 Oct;84(4):564-575. doi: 10.1002/ana.25322. Epub 2018 Sep 26.
To assess scalp electroencephalographic (EEG) patterns as possible biomarkers for an underlying focal cortical dysplasia (FCD) in patients with structural epilepsy.
Scalp electroencephalograms (EEGs) of epilepsy patients with histologically confirmed diagnosis of FCD type I or II (n = 71, age = 3-66 years, 28 female) and of controls with other underlying pathologies (n = 43, age = 2-60 years, 16 female) were retrospectively evaluated regarding the presence or absence of 12 scalp EEG patterns previously reported to be associated with FCD. Furthermore, 2 subgroups of these biomarkers with common characteristics were also analyzed. Each of the 12 biomarkers was tested for association with FCD by comparing the presence of each feature in FCD patients and controls using Fisher exact test.
A significant association with FCD as underlying etiology was found for 6 of 12 previously reported biomarkers. With decreasing odds ratios, these were continuous epileptiform discharges, 2 types of rhythmic epileptiform discharges, polyspikes, frequent rhythmic bursting epileptiform activity, and repetitive discharges as well as the subgroups containing repetitive activity and polyspikes, respectively. Presence of EEG biomarkers was independent of a visible underlying magnetic resonance imaging-visible lesion, and had similar prevalence with FCD I and II. Individual biomarkers had specificities of 65 to 98% and sensitivities of 17 to 61% for an underlying FCD, and combinations of EEG biomarkers achieved 100% specificity.
This study confirms that there are several surface EEG biomarkers significantly associated with an underlying cortical dysplasia. These biomarkers may aid in localizing suspicious brain regions and provide evidence for dysplastic brain tissue also in nonlesional patients of either histological FCD subtype. Ann Neurol 2018;84:564-575.
评估头皮脑电图（EEG）模式是否可作为结构性癫痫患者潜在局灶性皮质发育不良（FCD）的生物标志物。
回顾性评估经组织学证实为 FCD I 或 II 型（n=71，年龄 3-66 岁，28 例女性）和其他潜在病理学（n=43，年龄 2-60 岁，16 例女性）的癫痫患者的头皮脑电图（EEG）是否存在 12 种先前报道与 FCD 相关的头皮 EEG 模式。此外，还分析了具有共同特征的这两个生物标志物的两个亚组。使用 Fisher 精确检验比较 FCD 患者和对照组中每个特征的存在情况，以评估每个生物标志物与 FCD 的相关性。
发现 12 种先前报道的生物标志物中有 6 种与 FCD 作为潜在病因具有显著相关性。随着优势比的降低，这些标志物分别为连续癫痫样放电、2 种节律性癫痫样放电、多棘波、频繁节律性爆发性癫痫样活动以及重复性放电，以及分别包含重复性活动和多棘波的亚组。脑电图生物标志物的存在与可见的磁共振成像可见病变无关，在 FCD I 和 II 中具有相似的患病率。个体生物标志物对潜在 FCD 的特异性为 65%至 98%，敏感性为 17%至 61%，脑电图生物标志物的组合可达到 100%的特异性。
本研究证实，有几个表面 EEG 生物标志物与皮质发育不良有显著相关性。这些生物标志物可以帮助定位可疑的脑区，并为组织学上任何 FCD 亚型的非病变患者提供异常脑组织的证据。
