Lateralized periodic discharges (LPDs) are unilateral electroencephalography (EEG) waveforms, recurring at regular intervals. There has been a long-lasting debate about whether they represent ictal or interictal phenomena. Very few patients in the literature have been investigated with multimodal functional imaging techniques. Here, we present a 58-year-old male patient with symptomatic epilepsy who had cerebral venous sinus thrombosis in the right temporo-parietal area and dural arteriovenous fistula (dAVF) over the left fronto-parietal region. He developed acute speech disturbances and altered mental status after a generalized tonic–clonic seizure. Video-EEG monitoring (VEEGM) demonstrated LPDs over the left fronto-central area, overlapping in part with the dAVF. Diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) sequences revealed restricted diffusion compatible with cytotoxic edema, whereas single-photon emission computed tomography (SPECT) indicated hyperperfusion in the same region, leading to the conclusion that he was having possible nonconvulsive status epilepticus (NCSE). An increase in antiseizure medications led to gradual improvement in clinical status and the disappearance of LPDs.

侧向周期性放电 (LPD) 是单侧脑电图 (EEG) 波形，定期重复出现。关于它们是否代表发作期或发作间期现象一直存在长期争论。文献中很少有患者使用多模态功能成像技术进行研究。在这里，我们介绍了一名患有症状性癫痫的 58 岁男性患者，他在右侧颞顶叶区域有脑静脉窦血栓形成，在左侧额顶叶区域有硬脑膜动静脉瘘 (dAVF)。在全身强直-阵挛发作后，他出现了急性言语障碍和精神状态改变。视频脑电图监测 (VEEGM) 显示左额中央区域的 LPD，部分与 dAVF 重叠。弥散加权成像 (DWI) 和表观弥散系数 (ADC) 序列显示弥散受限与细胞毒性水肿相符，而单光子发射计算机断层扫描 (SPECT) 表明同一区域存在过度灌注，从而得出结论，他可能患有非惊厥性癫痫持续状态（NCSE）。抗癫痫药物的增加导致临床状态的逐渐改善和 LPD 的消失。