AIM Little is known about acute febrile status epilepticus-induced injury of extrahippocampal structures. To clarify the presence and clinical significance of acute extrahippocampal injuries, we performed diffusion-weighted imaging (DWI) in children immediately after prolonged febrile seizure (PFS). METHOD We performed a retrospective cohort study in children younger than 6 years old who visited one of two hospitals due to PFSs between January 2013 and October 2018. PFS was defined as a febrile seizure that persisted for 15 min or longer. We collected brain DWI data within 6 h of the end of PFS. When the initial DWI detected an abnormality, a follow-up DWI was performed a few days later. RESULTS The study population consisted of 101 patients with PFSs. DWI was performed within 6 h in 51 patients, while the remaining 50 patients did not undergo imaging because of good recovery of consciousness. Restricted cortical diffusion was evident in 9 (18%) patients on initial DWI. All of them underwent DWI within 100 min after PFS. Restricted cortical diffusion was associated with male sex, asymmetrical PFS symptoms, and a shorter duration between the end of the seizure and DWI, but was not associated with seizure duration. All cortical abnormalities had resolved on follow-up DWI of these patients within 72 h after the initial imaging, but ipsilateral hippocampal hyperintensity appeared in one patient. All 9 patients with restricted cortical diffusion were finally diagnosed with PFS and discharged without sequelae. CONCLUSIONS Some children with PFSs exhibit transient restricted diffusion in the regional cortex on DWI performed immediately after the end of PFS. These transient diffusion changes were not associated with unfavorable epileptic sequelae or neuroimaging in the short-term.

中文翻译：

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儿童长期高热惊厥后立即出现暂时性皮质扩散受限

目的 关于急性发热性癫痫持续状态引起的海马外结构损伤知之甚少。为了阐明急性海马外损伤的存在和临床意义，我们在长期热性惊厥 (PFS) 后立即对儿童进行了弥散加权成像 (DWI)。方法 我们对 2013 年 1 月至 2018 年 10 月期间因 PFS 访问过两家医院之一的 6 岁以下儿童进行了一项回顾性队列研究。 PFS 定义为持续 15 分钟或更长时间的热性惊厥。我们在 PFS 结束后 6 小时内收集了大脑 DWI 数据。当最初的 DWI 检测到异常时，几天后进行了后续的 DWI。结果 研究人群由 101 名 PFS 患者组成。51 名患者在 6 小时内进行了 DWI，而其余50名患者由于意识恢复良好而未进行影像学检查。在初始 DWI 中，9 名 (18%) 患者的皮质扩散受限。所有患者均在 PFS 后 100 分钟内接受 DWI。皮质扩散受限与男性、不对称 PFS 症状以及癫痫结束和 DWI 之间的持续时间较短有关，但与癫痫持续时间无关。所有皮质异常在这些患者的随访 DWI 中在初始成像后 72 小时内得到解决，但一名患者出现同侧海马高信号。9 例皮质弥散受限的患者最终均被诊断为 PFS，无后遗症出院。结论 一些 PFS 儿童在 PFS 结束后立即执行 DWI 时表现出区域皮层的短暂受限扩散。这些短暂的扩散变化与短期内不利的癫痫后遗症或神经影像学无关。