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.
Abstract
Purpose
Surgery is the treatment of choice for drug-resistant temporal lobe epilepsy (TLE) associated with hippocampal sclerosis (HS). We assessed whether interictal epileptiform discharges (IEDs) on early postoperative EEG predicted seizure outcome after surgery.
Methods
We retrospectively included consecutive patients aged >16 years who underwent surgery for drug-resistant TLE with pathologically confirmed HS at Pitié-Salpêtrière Hospital, Paris, between 2003 and 2023. Eligible patients had at least 1 year of follow-up and an early postoperative EEG performed within 1 month after surgery. IED frequency was classified as high frequency (≥1/min) or low frequency (<1/min). Favourable 1-year outcome was defined as ILAE class 1. Long-term worsening was defined as any increase in ILAE class after the 1-year visit.
Results
Among 168 patients, 131 (78.0%) were ILAE class 1 at 1 year. EEG was performed a median of 7 days after surgery. IEDs were present in 81 patients (48.2%), including 48 with low-frequency and 33 with high-frequency IEDs. EEG features, including IED presence and frequency, did not differ between patients with and without ILAE class 1 outcome at 1 year. During longer follow-up, high-frequency IEDs were associated with worsening compared with no IEDs in the whole cohort (HR 2.25, 95% CI 1.01-4.98; p=0.046) and among patients seizure-free at 1 year (HR 2.59, 95% CI 1.10-6.11; p=0.03). Low-frequency IEDs were not associated with worsening.
Conclusion
High-frequency IEDs on early postoperative EEG may identify patients at increased risk of long-term deterioration after surgery for HS-related TLE. Prospective studies are needed before modifying routine follow-up strategies.
The findings did not yield any statistically significant results in this regard, and it is crucial that patients undergo surgical evaluation without delay to achieve seizure control and improve cognitive function.
Günay Gül, Fulya Eren, Melek Kandemir Yilmaz et al.· Clinical neurology and neuro...· 0 citations
The model achieved high specificity in predicting long-term seizure recurrence, which supports its potential clinical utility for postoperative risk stratification and counseling rather than surgical exclusion and underscores the translational potential of network-level biomarkers to complement conventional predictors.
V.Yu. Karpychev, Rebecca W. Roth, William Yun et al.· Neurology· 0 citations
Abstract Objective Epileptic spasms (ES) in children carry a high risk of neurodevelopmental delay, yet predictors of long‐term surgical outcome remain incompletely defined. This study aimed to evaluate seizure outcomes following epilepsy surgery and to identify independent prognostic factors for postoperative recurrence. Methods This retrospective cohort study included 73 patients (47 males, 64%; median age at surgery: 37 months, IQR: 20–55.5) with drug‐resistant ES who underwent resective or ablative surgery at Guangdong Sanjiu Brain Hospital in China between January 2015 and September 2024, with regular follow‐up at least 12 months after epilepsy surgery. Independent predictors of recurrence were identified using multivariate Cox proportional hazards regression, and Kaplan–Meier analysis was performed to compare seizure‐free survival stratified by seizure duration (SD) and residual lesion status. Results Seizure‐free rates were 75.3% at 1 year and 55.1% at last follow‐up. Mean follow‐up was 61.36 ± 26.10 months (range: 12–132). Among malformation of cortical development (MCD) subtypes, focal cortical dysplasia (FCD) type II demonstrated the highest 5‐year seizure‐free rate (100%), whereas mild MCD (m‐MCD) showed the lowest (33.3%; p = 0.039). On multivariate Cox analysis, residual lesion on postoperative MRI was the strongest independent predictor of recurrence (HR = 5.13; 95% CI: 2.28–11.51; p < 0.001), followed by SD exceeding 36 months (HR = 2.49; 95% CI: 1.17–5.29; p = 0.018). Kaplan–Meier analysis confirmed a twofold difference in 5‐year seizure‐free survival between patients with duration ≤36 versus >36 months (73% vs. 36%; log‐rank p = 0.00069), and significantly better seizure‐free survival in patients without residual lesions (log‐rank p < 0.0001). Significance Complete lesion resection and early surgical intervention (SD ≤36 months) are independently associated with favorable long‐term seizure outcomes in children with drug‐resistant ES. Pathological subtype, particularly FCD type II, further refines prognostic stratification. These findings support prompt surgical referral and underscore the importance of achieving complete lesion removal to optimize postoperative seizure control. Plain Language Summary Some children develop a severe form of epilepsy called epileptic spasms that cannot be controlled with medication. In this study of 73 children who had brain surgery for this condition, more than half remained seizure‐free after 5 years. Children who had surgery earlier—before seizures had continued for 3 years—and those in whom the entire abnormal brain tissue was removed did significantly better in the long run. These findings suggest that referring children for surgery sooner rather than later can meaningfully improve their chances of living seizure‐free.
Hua Li, Yao Wang, Qiang Guo et al.· Epilepsia Open· 0 citations
OBJECTIVE
To describe 5-year mortality after status epilepticus (SE) and identify factors associated with long-term survival. We also validated the prognostic performance of the Age, Consciousness, Duration (ACD) score and evaluated long-term survival across etiological categories defined by the Lattanzi classification of acute symptomatic SE.
METHODS
Retrospective cohort analysis of a prospectively maintained database of consecutive patients ≥16 years of age with confirmed SE admitted to a tertiary epilepsy center (2011-2022). We excluded unclear diagnoses, hypoxic-anoxic etiologies, and incomplete follow-up. We recorded clinical variables and prognostic scores modified Status Epilepticus Severity Score (mSTESS), Epidemiology-based Mortality Status Epilepticus (EMSE), and Age, Consciousness, Duration (ACD). Mortality was assessed at discharge and annually up to 5 years.
RESULTS
We included 786 patients (mean age 63.4 years, 43.5% female). Five-year mortality was 50.3%, with 44.0% of deaths occurring within the first 2 years. Neurological causes accounted for 60.8% of deaths, and direct seizure-related causes represented 74.6% of neurological deaths. Independent predictors of higher long-term mortality were older age, higher premorbid mRS, absence of prior seizure history, comorbidity burden, systemic complications, and impaired consciousness during SE; convulsive and focal motor SE were associated with lower mortality risk. mSTESS and EMSE were associated with long-term mortality. In patients with less damaging etiologies, ACD predicted 5-year mortality (hazard ratio [HR] 1.163, 95% confidence interval [CI] 1.063-1.273; area under the curve [AUC] 0.717); ACD ≥10 corresponded to >50% 2-year mortality. Five-year mortality was 61.3% (acute-primary Central Nervous System (CNS) and 58.3% (acute-secondary CNS).
SIGNIFICANCE
SE carries substantial long-term mortality, particularly within the first 2 years. Neurological and seizure-related causes were the most frequent. The Lattanzi classification and the ACD score retained long-term prognostic value.
Manuel Alanís-Bernal, D. Campos-Fernández, L. Abraira et al.· Epilepsia· 0 citations
To evaluate clinical predictors of adaptive functioning in pediatric patients with drug-resistant epilepsy (DRE) and the impact of corpus callosotomy and vagus nerve stimulation (VNS) using the Vineland Adaptive Behavior Scales (VABS) during long-term follow-up. This retrospective observational cohort study included 37 pediatric patients with DRE who underwent callosotomy (n = 24) or VNS (n = 13) at the Ribeirão Preto Epilepsy Surgery Program, University of São Paulo, between 2007 and 2018. Adaptive functioning was assessed using the VABS at three time points: preoperative, postoperative I (mean 25 months), and postoperative II (mean 51 months). Seizure outcomes were classified according to the Engel scale. Statistical analyses included analysis of variance, Pearson correlation, linear regression, and a general linear model for repeated measures. All patients presented adaptive delay preoperatively, with discrepancies between chronological age and age-equivalent scores. Postoperatively, seizure reduction occurred in 70.2% of patients, with most achieving Engel class II–III outcomes. A reduction in antiseizure medication use was observed in 43.2% of patients. Adaptive functioning declined at the first postoperative assessment but gradually improved over time, particularly among patients with better seizure control. Statistical analyses demonstrated significant effects of postoperative time and seizure outcomes on adaptive functioning, with greater improvements in patients with favorable seizure control (F = 4.183; p = 0.024). Palliative surgical procedures for pediatric DRE are safe and associated with seizure reduction, decreased medication burden, and gradual improvement in adaptive functioning. Early surgical intervention may help minimize developmental decline and improve long-term adaptive outcomes.
Ana Valeria Duarte Oliveira, H. Machado, Ú. Thomé et al.· Child's Nervous System· 0 citations
OBJECTIVE
To determine whether postoperative reduction of anti-seizure medication (ASM) burden is associated with cognitive improvement after anterior temporal lobectomy (ATL) in seizure-free patients.
METHODS
We retrospectively analyzed data for adult patients with drug-resistant temporal lobe epilepsy who underwent unilateral ATL between March 2013 and January 2025. Analyses were restricted to patients achieving complete freedom from seizures (Engel Class I) at 1 year. ASM burden was quantified using the prescribed daily dose/defined daily dose ratio, and the reduction rate was calculated. Preoperative and 1-year postoperative neuropsychological outcomes, including full-scale intelligence quotient (FSIQ) and domain-specific indices, were assessed. The effect of ASM reduction on cognitive change was evaluated using a doubly robust estimation framework integrating inverse probability of treatment weighting with multivariable outcome regression. Robustness and potential dose-response relationships were assessed via sensitivity analyses, analysis of covariance (ANCOVA), and categorical modeling.
RESULTS
Fifty-seven seizure-free patients were included in the primary analysis (median age at surgery, 32 years; 33 female). Greater ASM reduction was significantly associated with improved working memory (WM) (β = .066, p = .001). A positive but non-significant trend was observed for FSIQ (β = .021, p = .062). A dose-response relationship was identified, with greater ASM reduction associated with progressively greater improvement in WM (p = .013). Findings were consistent across sensitivity and ANCOVA analyses.
SIGNIFICANCE
Postoperative ASM reduction was associated with domain-specific cognitive improvement following ATL, particularly in WM. These findings support ASM tapering as a potentially modifiable factor influencing postoperative cognitive outcomes.
Kazushi Ukishiro, S. Osawa, M. Ogawa et al.· Epilepsia· 0 citations