Currently, the relevance of EEG measurements in acute stroke patients is considered low in clinical practice. However, recent studies on the predictive value of EEG measurements after stroke for various outcomes may increase the role of EEG in patients with stroke. We aimed to review the current literature on the utility of EEG measurements after stroke as a tool to predict outcome and complications, focusing on studies in which the EEG measurement was performed in the acute phase after the event and in which long-term outcome measures were reported. In our literature review, we identified 4 different outcome measures (functional outcome, mortality, development of post-stroke cognitive decline, and development of post-stroke epilepsy) where studies on the utility of acute EEG measurements exist. There is a large body of evidence for the prediction of functional outcome, in which a multitude of associated quantitative and qualitative EEG parameters are described. In contrast, only few studies focus on mortality as outcome parameter. We found studies of high methodical quality on the prediction of post-stroke cognitive decline, though the number of patients in these studies often was small. The role of EEG as a prediction tool for seizures and epilepsy after stroke could increase after a recently published study, especially if its result can be incorporated into already existing post-stroke epilepsy prediction tools. In summary, EEG is useful for the prediction of functional outcome, mortality, development of post-stroke cognitive decline and epilepsy, even though there is a discrepancy between the large amount of studies on EEG in acute stroke patients and its underuse in clinical practice.

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Objective In focal epilepsy, data on the etiology‐specific response to antiseizure medication (ASM) are surprisingly sparse. In this study, we sought to reappraise whether seizure outcome of pharmacological treatment is linked to the underlying etiology. Furthermore, we assessed ASM load with respect to the cause of epilepsy. Methods Data were retrospectively obtained from the electronic database of the three sites of an academic adult epilepsy outpatient clinic. For each patient, presumed cause of epilepsy was categorized into one of nine etiological groups. Individual drug loads were calculated according to the 2020 World Health Organization Center for Drug Statistics Methodology ATC/DDD Index. Univariate and multivariate analyses were conducted to explore the association between different etiologies and outcome regarding 12‐month seizure freedom as well as ASM load. Results A total of 591 patients with focal epilepsy were included in the final analysis. Ischemic stroke was the etiology with the highest rate of 12‐month terminal seizure freedom (71.2%, 95% confidence interval [CI] = 57.9–82.2) and, considering all etiological groups, was an independent predictor of seizure freedom (odds ratio = 2.093, 95% CI = 1.039–4.216). The lowest rates of seizure freedom were observed in patients with hippocampal sclerosis (28.2%, 95% CI = 15.0–44.9) and malformation of cortical development (16.7%, 95% CI = 2.1–48.4). In patients with ischemic stroke, median ASM load (1.0, interquartile range [IQR] = .5–1.8) was significantly lower compared to that in patients with hippocampal sclerosis (median = 1.8, IQR = 1.2–3.0, p = .008) and brain tumors (median = 1.7, IQR = .7–3.2, p = .049). Significance Response to treatment with ASM is highly etiology‐specific and best in patients with epilepsy due to ischemic stroke. Interestingly, this most favorable treatment outcome can be achieved by the lowest ASM load considering all etiological groups. In focal epilepsy, etiology should be taken into account when counseling patients about their expected seizure outcome with pharmacological treatment and when tailoring initial ASM doses.