Lennox–Gastaut syndrome (LGS) is a severe form of childhood onset epileptic encephalopathy characterized by multiple drug-resistant seizures, cognitive impairment, and diffuse slow spike and wave (SSW), and generalized paroxysmal fast activity (GPFA) on electroencephalogram (EEG). Systematic review following the Preferred Reporting Items for Systematic Reviews and Meta Analysis (PRISMA) guidelines was done to investigate EEG findings in LGS. PubMed and MEDLINE were systematically searched for English-language studies published until15th may 2023. Original articles and research with patients between age group 1–30 years, and studies with description of EEG findings were included. Search identified 20 studies with 1167 patients. In this analysis 62.6 % of patients were male. The median age was 9.6 years. Etiology was structural abnormality in 42.6 %, genetic in 8.7 % but was unknown in 48.7%. Tonic seizures (74.5 %) were most frequent followed by atypical absences (44.3 %), myoclonic (39.2 %), generalized (38.5 %), atonic (34.8 %), epileptic spasm (15.9 %), focal (11.4 %) and non-convulsive status epilepticus (7.0 %). Out of 20 studies, only 15 studies mentioned GPFA in 46.6 % patients and SSW in 91.7 % patients. Unilateral and focal discharges were more common in patients with unilateral structural abnormalities. Seizure discharges on EEG longer than 10 second duration correlated with seizure diary counts. Combination of atonic, tonic, and atypical absence seizures correlated with SSW, and myoclonic seizures correlated with GPFA. EEG helps in diagnosis and prognosis of LGS. SSW is present in almost all EEG, and GPFA in 46.6 % patients. Longer duration of SSW discharges and disorganized background are associated with poor outcome.

中文翻译：

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Lennox-Gastaut 综合征脑电图检查结果的系统评价


Lennox-Gastaut 综合征 (LGS) 是一种严重的儿童期癫痫性脑病，其特征是多次耐药性癫痫发作、认知障碍、弥漫性慢棘慢波 (SSW) 以及脑电图 (EEG) 上的全身阵发性快活动 (GPFA) 。按照系统评价和荟萃分析的首选报告项目 (PRISMA) 指南进行系统评价，以调查 LGS 的脑电图结果。 PubMed 和 MEDLINE 系统地检索了截至 2023 年 5 月 15 日发表的英语研究。其中包括针对 1-30 岁年龄组患者的原创文章和研究，以及描述脑电图结果的研究。搜索发现了 20 项研究，涉及 1167 名患者。在此分析中，62.6% 的患者为男性。中位年龄为 9.6 岁。 42.6% 的病因是结构异常，8.7% 的病因是遗传，但 48.7% 的病因未知。强直性发作 (74.5 %) 最常见，其次是非典型失神 (44.3 %)、肌阵挛 (39.2 %)、全面性 (38.5 %)、失张力 (34.8 %)、癫痫性痉挛 (15.9 %)、局灶性 (11.4 %) 和非癫痫性发作。 -惊厥性癫痫持续状态（7.0%）。在 20 项研究中，只有 15 项研究在 46.6% 的患者中提到了 GPFA，在 91.7% 的患者中提到了 SSW。单侧和局灶性放电在单侧结构异常的患者中更为常见。脑电图上持续时间超过 10 秒的癫痫放电与癫痫日记计数相关。失张力、强直和非典型失神发作的组合与 SSW 相关，肌阵挛发作与 GPFA 相关。脑电图有助于 LGS 的诊断和预后。 SSW 存在于几乎所有 EEG 中，GPFA 存在于 46.6% 的患者中。 SSW 放电持续时间较长和背景混乱与不良结果相关。