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Malformations of cortical development (MCD) represent a group of rare diseases with severe clinical presentation as epileptic and pharmacoresistant encephalopathies. Morphological studies in tissue from MCD patients have revealed reduced GABAergic efficacy and increased intracellular chloride concentration in neuronal cells as important pathophysiological mechanisms in MCD. Also, in various animal models, alterations of GABAergic inhibition have been postulated as a predominant factor contributing to perilesional hyperexcitability. Along with this line, the NKCC1 inhibitor bumetanide has been postulated as a potential drug for treatment of epilepsy, mediating its antiepileptic effect by reduction of the intracellular chloride and increased inhibitory efficacy of GABAergic transmission. In the present study, we focused on the focal freeze-lesion model of MCD to compare antiepileptic drugs with distinct mechanisms of action, including NKCC1 inhibition by bumetanide. For this purpose, we combined electrophysiological and optical methods in slice preparations and assessed the properties of seizure like events (SLE) induced by 4-aminopyridine. In freeze-lesioned but not control slices, SLE onset was confined to the perilesional area, confirming that this region is hyperexcitable and likely triggers pathological activity. Bumetanide selectively reduced epileptic activity in lesion-containing slices but not in slices from sham-treated control rats. Moreover, bumetanide caused a shift in the SLE onset site away from the perilesional area. In contrast, effects of other antiepileptic drugs including carbamazepine, lacosamide, acezatolamide and zonisamide occurred mostly independently of the lesion and did not result in a shift of the onset region. Our work adds evidence for the functional relevance of chloride homeostasis in the pathophysiology of microgyrus formation as represented in the focal freeze-lesion model. Further studies in different MCD models and human tissue will be required to validate the effects across different MCD subtypes and species and to assess the translational value of our findings., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objective: To analyze the significance of intracranial electroencephalography (iEEG) parameters such as seizure onset patterns (SOP) and size of seizure onset zone (SOZ) with respect to prediction of seizure freedom after resective epilepsy surgery., Methods: All patients who underwent iEEG with subdural electrodes between January 2006 and December 2015 in our epilepsy-center were included. Various iEEG parameters were retrospectively analyzed regarding their predictive value to post-operative seizure freedom. Furthermore, associations of specific SOPs with underlying histopathology and brain regions of the SOZ were examined., Results: Eighty-one patients (34 female) with 324 seizures were assessed. Low-voltage fast activity (37%) and sharp activity <13 Hz (30%) were the most frequent SOPs. Focal SOZ (≤2 cm) was the only iEEG parameter independently associated with 1-year post-operative seizure freedom (OR 4.1, 95% CI 1.433-11.679). While no SOP was linked to specific histopathologies, some associations between SOPs and anatomical regions of SOZ were found., Conclusions: A circumscribed SOZ, but no specific SOP was predictive for seizure freedom after epilepsy surgery., Significance: Intracranial EEG may be helpful to predict post-operative seizure freedom. Multicenter studies with larger numbers of patients are required to reliably assess the significance of specific SOPs for successful resective epilepsy surgery., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Stroke is one of the commonest causes of seizures and epilepsy, mainly among the elderly and adults. This seminar paper aims to provide an updated overview of post-stroke seizures and post-stroke epilepsy (PSE) and offers clinical guidance to anyone involved in the treatment of patients with seizures and stroke. The distinction between acute symptomatic seizures occurring within seven days from stroke (early seizures) and unprovoked seizures occurring afterwards (late seizures) is crucial regarding their different risks of recurrence. A single late post-stroke seizure carries a risk of recurrence as high as 71.5% (95% confidence interval: 59.7-81.9) at ten years and is diagnostic of PSE. Several clinical and stroke characteristics are associated with increased risk of post-stroke seizures and PSE. So far, there is no evidence supporting the administration of antiepileptic drugs as primary prevention, and evidence regarding their use in PSE is scarce.

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.

The development of seizures is a common complication in patients with stroke. A recent study suggests that electroencephalography (EEG) could be useful to predict the occurrence of seizures after stroke. However, EEG is not routinely performed in the follow-up after stroke. We present the design and proof of concept of a large prospective cohort study in which we seek to evaluate the predictive usefulness of a single dry cap EEG measurement in the acute phase after stroke or transient ischemic attack (TIA) with respect to the development of poststroke epilepsy (PSE). In patients with ischemic stroke (IS), TIA, or intracerebral hemorrhage (ICH), an acute EEG measurement using a dry cap electrode EEG (dEEG) system is performed within 7 days of symptom onset. Electroencephalography data will be analyzed quantitatively and qualitatively looking for background asymmetry, different band power ratios, and epileptiform activity. The development of seizures will be assessed repeatedly during the first 2 years after stroke or TIA using a validated questionnaire. Results from the pilot phase of 11 patients showed that the dry cap EEG measurements in patients with acute stroke and TIA are feasible. In comparison with conventional EEG, a higher proportion of noise and artifacts was detected. This article is part of the Special Issue "Seizure & Stroke"., Competing Interests: Declaration of competing interest JD, TK, MA, and JW declared no conflicts of interest with respect to the research, authorship, and/or publication of this article. MH received speaker's honoraria and/or consultancy fees within the last 3 years from Bial, Desitin, Eisai, GW Pharmaceuticals, LivaNova, Medtronic, Novartis, and UCB., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: Despite the obvious advantages of resective surgery in patients with drug-resistant focal epilepsy, namely high probability of seizure freedom, decreased mortality, and increased quality of life, referral rates from physicians and approval rates by patients for presurgical assessment remain constantly low., Methods: In the outpatient clinics of a tertiary epilepsy center, checklists were implemented asking treating epileptologists whether they recommended presurgical evaluation with noninvasive video-electroencephalographic monitoring to adult patients with drug-resistant focal epilepsy and asking respective patients whether they followed this recommendation., Results: Of 185 eligible patients, 80 (43%) were recommended presurgical evaluation by their epileptologists, and 24 (30%) of these patients consented. Nineteen of all patients (10%) actually underwent noninvasive presurgical assessment, and nine of these eventually proceeded to resection. The most frequent reason for nonreferral by epileptologists was their subjective appraisal of seizure frequency as low (31%), whereas patients declined most often due to overall fear of brain surgery (50%). Variables independently associated with nonreferral by epileptologists comprised older age of patients at questioning (odds ratio [OR] = 1.03), no previous evaluation for epilepsy surgery (OR = 4.04), the presence of legal guardianship (OR = 4.29), and ≥11 years of professional experience by the treating epileptologist (OR = 4.62). Independent predictors for patients' rejection of presurgical evaluation were older age at questioning (OR = 1.08), lifetime number of antiepileptic drugs ≥ 5 (OR = 4.47), presence of focal aware seizures (OR = 4.37), and absence of focal seizures with impaired awareness (OR = 11.24)., Significance: In both epileptologists and patients with difficult-to-treat epilepsy, we found high decision rates against presurgical assessment. Some reasons given by physicians for not recommending presurgical evaluation to patients may be understandable; others need further exploration. On the patients' side, early and thorough counseling on risks and benefits of epilepsy surgery is necessary to increase understanding and acceptance., (Wiley Periodicals, Inc. © 2019 International League Against Epilepsy.)

Objectives: To assess the effectiveness and safety/tolerability of eslicarbazepine acetate (ESL) monotherapy in clinical practice in Europe., Materials and Methods: Euro-Esli was a pooled analysis of 14 European clinical practice studies. Responder rate (≥50% seizure frequency reduction) and seizure freedom rate (seizure freedom at least since prior visit) were assessed after 3, 6 and 12 months of ESL treatment and at last visit. Adverse events (AEs) and AEs leading to ESL discontinuation were assessed throughout follow-up. A subanalysis was conducted to assess outcomes for patients treated initially with ESL monotherapy and for patients treated at the last visit with ESL monotherapy., Results: ESL was used as monotherapy in 88/2045 (4.3%) patients initially and in 229/1340 (17.1%) patients at the last visit. At 12 months, responder and seizure freedom rates were 94.1% and 88.2%, respectively, in patients treated initially with ESL monotherapy, and 93.2% and 77.4%, respectively, in patients treated at the last visit with ESL monotherapy. Corresponding values for patients treated initially with ESL adjunctive therapy were 74.8% and 39.0%, respectively; and for patients treated at the last visit with ESL adjunctive therapy, corresponding values were 70.4% and 25.9%, respectively. Safety and tolerability were generally comparable in patients treated with ESL as monotherapy or adjunctive therapy. The most commonly reported AEs (≥5% of patients in any group) were dizziness, somnolence, instability/ataxia, and fatigue., Conclusions: These clinical practice data support the use of ESL as monotherapy, as well as adjunctive therapy, for focal-onset seizures, complementing evidence from clinical trials., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The Euro-Esli study was an exploratory pooled analysis of data from 14 European clinical practice studies, which was conducted to audit the real-world effectiveness, safety, and tolerability of eslicarbazepine acetate (ESL) as an adjunctive treatment for partial-onset seizures. Retention and effectiveness were assessed after 3, 6, and 12 months of ESL treatment, and at the final visit. Safety and tolerability were assessed throughout ESL treatment by evaluating adverse events (AEs) and ESL discontinuation due to AEs. Data from 2058 patients (52.1% male; mean age 44.0 years) were included. All 2058 patients were assessed for safety and 1975 (96.0%) patients were assessed for effectiveness. After 12 months, retention, responder (≥50% seizure frequency reduction), and seizure freedom rates were 73.4, 75.6, and 41.3%, respectively. AEs were reported for 34.0% of patients and led to discontinuation in 13.6% of patients. The most frequently reported AEs were dizziness (6.7% of patients), fatigue (5.4%), and somnolence (5.1%). No unexpected safety signals emerged over a median duration of follow-up of >5 years. Subgroup analyses revealed that ESL was significantly more effective in patients aged ≥65 versus <65 years, in patients who were not receiving treatment with other sodium channel blockers versus those who were receiving treatment with other sodium channel blockers, and in patients who were receiving <2 versus ≥2 concomitant antiepileptic drugs at baseline. Euro-Esli is the largest ESL clinical practice study conducted to date. This study provides strong and reassuring evidence of ESL's safety profile, and complements the data from clinical trials.

Objectives: Juvenile myoclonic epilepsy (JME) is the most common idiopathic generalized epilepsy subsyndrome, contributing to approximately 3% to 11% of adolescent and adult cases of epilepsy. However, little is known about the long-term medical evolution of this clinical entity. The aim of this study was to analyze long-term outcome in a clinically well-defined series of patients with JME for seizure evolution and predictors of seizure outcome., Methods: In this retrospective cohort study, we analyzed seizure outcome in 66 patients who had JME, were treated at the Department of Neurology, Charité-Universitätsmedizin Berlin, and were initially diagnosed by a single senior epileptologist., Results: After a mean follow-up time of 44.6 years (20-69 years), 59.1% of patients remained free of seizures for at least 5 years before the last contact. Among the seizure-free patients, 28 (71.8%) were still taking antiepileptic drugs and 11 (28.2%) were off medication for at least the last 5 years. We identified manifestation of additional absence seizures at onset of JME as an independent predictor of an unfavorable outcome regarding seizure freedom., Conclusions: A significant proportion of patients with JME were seizure-free and off antiepileptic drug therapy in the later course of their disorder. Patients with JME and additional absence seizures might represent a different JME subtype with a worse outcome.

Episodes of psychogenic nonepileptic status epilepticus (PNESE) characterized by pronounced generalized motor features were compared with those of refractory generalized convulsive status epilepticus. Patients with PNESE were younger, had port systems implanted more frequently, received higher doses of benzodiazepines until seizure termination or respiratory failure, and had lower serum creatine kinase levels.

Neuronal consequences of recurrent single epileptic seizures have been discussed controversially for some time. Various cross-sectional magnetic resonance imaging (MRI) studies have shown a positive correlation between the severity of epilepsy and the extent of hippocampal damage. However, the open question whether recurrent epileptic seizures induce hippocampal structural pathology can be assessed only in longitudinal studies. The few recent follow-up studies have revealed conflicting results. In the current MRI study we have employed volumetry and T2 relaxometry to quantify hippocampal structural changes of patients with chronic partial epilepsies over a period of 3 years. Our main findings demonstrate that these patients who experience continuing epileptic seizures do no show any development of new pathology or any relevant deterioration of pre-existing hippocampal structural lesions. This argues against the assumption that recurrent epileptic seizures cause or increase structural hippocampal damage.

Objectives: To describe incidence, risk factors, and treatment of poststroke epilepsy (PSE) in Germany based on claims data. Methods: Retrospective analysis of claims data from a German public sickness fund (AOK PLUS). Patients with acute stroke hospitalizations from January 01, 2011 and December 31, 2015 (index hospitalization) were followed for 12–72 months. Outcomes included incidence of PSE (patients with ≥2 seizure claims [during/after index hospitalization], or ≥1 seizure claim after index hospitalization), multivariate Cox‐regression analyses of time to seizure claim and death after index stroke hospitalization discharge, and antiepileptic drug (AED) treatment. Results: Among 53 883 patients with stroke (mean follow‐up of 829.05 days [median 749]), 6054 (11.24%) had ≥1 seizure claim (mean age 73.95 years, 54.18% female). 2130 (35.18%) patients had a seizure claim during index hospitalization (indicative of acute symptomatic seizures). Estimated incidence of PSE (cases/1000 patient‐years) was 94.49 within 1 year. Risk of seizure claim following hospital discharge was higher in patients with hemorrhagic stroke (hazard ratio [HR] =1.13; p <.001) vs those with cerebral infarction. Seizure claim during index hospitalization was a risk factor for seizure claims after hospital discharge (HR =6.97; p <.001) and early death (HR =1.78; p <.001). In the first year of follow‐up, AEDs were prescribed in 73.75% of patients with seizure claims. Conclusions: Incidence of PSE was in line with previous studies. Hemorrhagic stroke and seizure claim during index hospitalization were risk factors for seizure claims after hospital discharge. Most patients with seizure claims received AED treatment. [ABSTRACT FROM AUTHOR]

Neuromodulative treatment options are warranted in patients with difficult-to-treat epilepsy. However, acquisition of controlled data on deep brain stimulation has so far been achieved only for the centromedian and anterior thalamic nucleus. In a case series of four patients with intractable partial epilepsy, a randomized controlled cross-over protocol was used to get insight into efficacy and safety of 3-month nucleus accumbens stimulation. Seizure frequency, neurocognitive testing, 'Liverpool Seizure Severity Score,' 'Quality of Life in Epilepsy Inventory,' 'Beck Depression Inventory,' and 'Mini International Neuropsychiatric Interview' were obtained at every visit. In a subsequent open-label phase, nucleus accumbens stimulation responders underwent concomitant anterior thalamic nucleus stimulation, whereas nonresponders received solely thalamic stimulation. Under nucleus accumbens stimulation, three of four patients had ≥50% reduction in frequency of disabling seizures without further improvement with additional anterior thalamic nucleus stimulation. Patient-reported outcome and neurocognitive testing remained unchanged. Accumbens stimulation is safe and seems to be a suitable option in intractable partial epilepsy. The current findings require substantiation by an adequately powered multicenter study. [ABSTRACT FROM AUTHOR]