Beyond seizures: understanding adaptive functioning in drug-resistant epilepsy in patients undergoing palliative surgery

The association between the degree of intraoperative bisynchronization blockade and drop attack freedom after corpus callosotomy in pediatric patients: a comparative cohort study.

OBJECTIVE The aim of this study was to evaluate the prognostic value of intraoperative EEG during corpus callosotomy (CC) in pediatric patients with drug-resistant epilepsy (DRE), with a particular focus on bisynchronization blockade and its correlation with long-term seizure outcomes. METHODS A retrospective review was performed of pediatric patients with DRE and injurious drop attacks who underwent CC between 2005 and 2024. Patients were stratified into three groups based on intraoperative scalp EEG findings: 1) > 50% bisynchronization blockade, 2) < 50% blockade, and 3) absent bisynchronization. Baseline clinical characteristics, surgical approach, and extent of CC were recorded. Seizure outcomes were assessed using Engel and International League Against Epilepsy (ILAE) classifications with a minimum follow-up of 1 year. Whether atonic seizures resolved postoperatively was also evaluated. Group comparisons were performed using Fisher's exact test and Kruskal-Wallis rank-sum testing. RESULTS Forty-six patients met the inclusion criteria. The majority underwent complete CC (65%), most via an open approach (67%). At 1 year, freedom from atonic seizures (ILAE class 1Engel class I) was highest in the > 50% blockade group (70.0%) compared with the < 50% blockade (40.0%) and absent bisynchronization (25%) groups (p = 0.042). At last follow-up (mean 5.3 years), the > 50% blockade group similarly achieved significantly higher rates of atonic seizure freedom (ILAE class 1/Engel class I, 76%) compared with 0% in the < 50% blockade and 25% in the absent bisynchronization groups (p < 0.001). Outcomes for total seizure freedom varied and did not reach statistical significance between groups. CONCLUSIONS Achieving > 50% intraoperative bisynchronization blockade during CC was strongly associated with improved long-term atonic seizure freedom. These findings support the role of intraoperative EEG as a prognostic marker of effective seizure control.

Postoperative reduction of anti-seizure medication is associated with cognitive improvement in seizure-free patients after anterior temporal lobectomy.

Postoperative ASM reduction was associated with domain-specific cognitive improvement following ATL, particularly in WM, which support ASM tapering as a potentially modifiable factor influencing postoperative cognitive outcomes.

Long-term neuropsychiatric outcomes after neuromodulation in epilepsy patients: a systematic review and meta-analysis.

Longitudinal Bayesian analysis of lobe-specific cognitive outcomes after pediatric epilepsy surgery.

Epilepsy surgery preserved intellectual functioning, particularly in FL and PC procedures, however, persistent VCI decline in H and TL groups suggests effects on verbal abilities associated with temporal lobe involvement, and group-level trajectories rather than individual outcomes.

Long-term prognostic value of early post-operative electroencephalogram in patients with drug-resistant temporal lobe epilepsy associated with hippocampal sclerosis.

High-frequency IEDs on early postoperative EEG may identify patients at increased risk of long-term deterioration after surgery for HS-related TLE, and prospective studies are needed before modifying routine follow-up strategies.

Comparative multicenter evaluation of thalamic neuromodulation for treatment-resistant epilepsy in children.

OBJECTIVE Use of neuromodulation strategies targeting thalamic nuclei, including deep brain stimulation (DBS) and responsive neurostimulation (RNS), for treatment of pediatric drug-resistant epilepsy (DRE) is increasing, despite limited evidence for efficacy and safety. We present the initial results from the Comparative Multicenter Evaluation of Thalamic Neuromodulation for Treatment-Resistant Epilepsy in Children consortium, which was created to study thalamic modulation in children with DRE. METHODS We performed a retrospective cohort study of children who underwent thalamic DBS or RNS for DRE between January 2015 and December 2024 across 12 centers. Primary outcomes were percent seizure reduction, Engel class, and responder rates (>50% seizure reduction) at 3, 6, and 12 months postoperatively. Secondary outcomes included antiseizure medications and surgical complications. Differences were quantified using ordinal logistic regression, generalized estimating equations with center clustering, and mixed-effects models. Stratified analyses were performed by thalamic target (centromedian vs. anterior nucleus) and epilepsy diagnosis (Lennox-Gastaut syndrome, generalized, focal, and multifocal). RESULTS Among the 221 included patients (111 DBS, 110 RNS) included, DBS and RNS achieved comparable Engel scores and 12-month responder rates, but different temporal trajectories were observed. There was a significant device × time interaction (odds ratio = 1.10/month, 95% confidence interval = 1.01-1.20, p = .04), with RNS response rates increasing from 26.9% at 3 months to 55.6% at 12 months (paired p < .001) but with DBS response rates reaching 41.7% at 3 months and remaining comparatively stable over time. DBS achieved significantly higher 12-month seizure freedom (9.5% vs. 1.2%, p = .03). Neither thalamic target selection nor diagnosis predicted seizure outcome. Safety profiles were equivalent. SIGNIFICANCE This multicenter analysis provides pediatric-specific data to inform surgical indications, device selection, and preoperative counseling. DBS and RNS were effective for treatment of pediatric DRE, with equivalent 12-month seizure outcomes but different temporal trajectories. DBS provided earlier seizure control and higher rates of overall seizure freedom.