颞叶良性脑电图变异型脑电-临床研究进展

头皮脑电图因操作便捷、无创、可重复等特点,广泛应用于癫痫及其他脑病的诊断与治疗。长期的临床实践发现有诸多脑电图异常放电模式与临床癫痫发作无明确关联性,可能属于良性变异型,亦可能是颅内异常放电,至今尚无明确定论。本文拟对颞叶常见的良性变异型研究进展进行概述,以理清长期以来的争议点,为相关基础与临床研究奠定基础。

Effect of levetiracetam and valproate on late‑onset post‑traumatic seizures

Background To compare the preventive effects of levetiracetam and valproate on late-onset post-traumatic seizures in patients with traumatic brain injury(TBI).Methods A total of 95 patients with TBI were recruited from 2017 to 2020.They were randomized into three groups:levetiracetam(LEV)group(n=30)receiving LEV treatment(500 mg,bid,po);valproate group(n=32)receiving sodium valproate(500 mg/d,once daily,po);and control group(n=33)receiving no anti-seizure medication.LEV and valproate were given to corresponding groups within seven days after TBI,and the administration lasted for one month.The incidence of epilepsy and adverse events were evaluated at 7 days and 12 months post-TBI.Results The cumulative incidences of late post-traumatic seizures at the 12-month follow-up in the LEV,valproate,and control groups were 3.33%,12.50%and 15.63%,respectively.The cumulative incidence of late post-traumatic seizures in the LEV group was significantly lower than those in the valproate and control groups(P<0.05).The cumulative incidence of late post-traumatic seizure in the valproate group was not significantly different from that in the control group(P>0.05).Conclusions LEV can reduce the cumulative incidence of late post-traumatic seizures,whereas valproate can not.

Ictal-interictal continuum:a review of recent advancements

Continuous electroencephalogram(cEEG)has become an indispensable technique in the management of critically ill patients for early detection and treatment of non-convulsive seizures(NCS)and non-convulsive status epilepticus(NCSE).It has also brought about a renaissance in a wide range of rhythmic and periodic patterns with heterogeneous frequency and morphology.These patterns share the rhythmic and sharp appearances of electrographic seizures,but often lack the necessary frequency,spatiotemporal evolution and clinical accompaniments to meet the definitive criteria for ictal patterns.They may be associated with cerebral metabolic crisis and neuronal injury,therefore not clearly interictal either,but lie along an intervening spectrum referred to as ictal-interictal continuum(IIC).Generally speaking,rhythmic and periodic patterns are categorized as interictal patterns when occurring at a rate of<1Hz,and are categorized as NCS and NCSE when occurring at a rate of>2.5 Hz with spatiotemporal evolution.As such,IIC commonly includes the rhythmic and periodic patterns occurring at a rate of 1–2.5 Hz without spatiotemporal evolution and clinical correlates.Currently there are no evidence-based guidelines on when and if to treat patients with IIC patterns,and particularly how aggressively to treat,presenting a challenging electrophysiological and clinical conundrum.In practice,a diagnostic trial with preferably a non-sedative anti-seizure medication(ASM)can be considered with the end point being both clinical and electrographic improvement.When available and necessary,correlation of IIC with biomarkers of neuronal injury,such as neuronal specific enolase(NSE),neuroimaging,depth electrode recording,cerebral microdialysis and oxygen measurement,can be assessed for the consideration of ASM treatment.Here we review the recent advancements in their clinical significance,risk stratification and treatment algorithm.

Sudden unexpected death after acute symptomatic seizures in a patient on mechanical ventilation

Background:The mechanism of sudden unexpected death in epilepsy remains poorly understood.Seizure induced cardiac arrhythmia,central and obstructive apneas have been proposed as possible causes of death.Here we report a unique case of seizure related sudden unexpected death in a patient whose airway was fully protected by intubation and mechanic ventilation in the absence of fatal cardiac arrhythmia.Case presentation:A 70-year-old woman was undergoing mechanical ventilation and videoelectroencephalography(EEG)monitoring following two convulsive seizures with ictal hypoventilation and hypoxemia.Several hours after intubation,she suffered another generalized tonic clonic seizure lasted for 3 min and developed postictal generalized EEG suppression in the presence of stable vital signs with SpO2>90%.EEG suppression persisted throughout the postictal phase.There was a significant fluctuation of systolic blood pressure between 50 and 180 mmHg with several bouts of hypotension<60 mmHg.She remained unresponsive after the convulsive seizure and died of diffuse cerebral edema 12 h later.Autopsy revealed no clear cause of death,except for possible hypoxic and ischemic injury leading to the diffuse cerebral edema.Conclusion:Given the reliable periictal airway protection,neither seizure induced central apnea nor obstructive apnea appeared to be the direct cause of death in this unique case.In the absence of fatal cardiac arrhythmia,diffuse cerebral edema secondary to seizure-induced autonomic dysfunction,hypotension and hypoxemia might be the cause of death,highlighting the etiological heterogeneity of sudden unexpected death in epilepsy.