Epilepsy surgery in pediatric intractable epilepsy with destructive encephalopathy

Seizure-type-specific treatment responses in Lennox-Gastaut Syndrome: A comprehensive review of pharmacological, neuromodulatory, dietary, and surgical therapies

Lennox-Gastaut Syndrome (LGS) is a severe developmental and epileptic encephalopathy characterized by multiple drug-resistant seizure types, presenting significant challenges for treatment. This comprehensive review examines seizure-type-specific response patterns to various therapeutic interventions in LGS. We conducted an extensive literature review of randomized controlled trials, observational studies, and real-world evidence, covering research up to February 2025. Our analysis shows that atonic seizures respond particularly well to corpus callosotomy (CC) and Vagus Nerve Stimulation (VNS), with CC demonstrating superior efficacy. Generalized tonic-clonic seizures (GTCS) show favorable responses to antiseizure medications (ASMs) such as felbamate, lamotrigine, topiramate, fenfluramine, lacosamide, and perampanel. Myoclonic seizures tend to respond better to clonazepam, topiramate, zonisamide, brivaracetam, and perampanel, but may show limited responsiveness to neuromodulation and CC. Atypical absence seizures may respond to valproate, topiramate, and rufinamide, but show poor responses to brivaracetam and perampanel. The ketogenic diet and resective epilepsy surgery demonstrate broad efficacy across seizure types, although specific data for each type remain limited. VNS is most effective for atonic and tonic seizures, with less consistent responses in GTCS and focal seizures. Emerging neuromodulation techniques, including deep brain stimulation (DBS) and responsive neurostimulation (RNS), show promise, particularly for tonic and GTCS, but further investigation is needed. This review underscores the importance of tailoring treatment to predominant seizure types and calls for more rigorous, seizure-type-specific outcome reporting in future clinical trials, along with the need for long-term studies. The findings advocate for a precision, network-based approach to treatment, where therapeutic decisions are guided by individual seizure patterns and supported by evidence-based, seizure-type-specific efficacy data.

Cognitive and behavioral impact of antiseizure medications, neuromodulation, ketogenic diet, and surgery in Lennox-Gastaut syndrome: A comprehensive review

Lennox-Gastaut syndrome (LGS) is a severe developmental and epileptic encephalopathy marked by drug-resistant seizures and profound cognitive and behavioral impairments, with nearly 95% of individuals affected by moderate to severe intellectual disability. This review comprehensively explores the cognitive and behavioral impacts of current treatment options for LGS, including antiseizure medications (ASMs), neuromodulation strategies, the ketogenic diet, and surgical interventions. Given the limited availability of LGS-specific data for several ASMs, the evidence base is supplemented with findings from general epilepsy populations and individuals with epilepsy and intellectual disabilities. The evidence reveals that ASMs exert varied cognitive and behavioral effects in LGS. Medications such as valproate, lamotrigine, cannabidiol, fenfluramine, levetiracetam, brivaracetam, felbamate, and rufinamide generally support cognitive stability, while topiramate and zonisamide are associated with cognitive challenges. Behavioral outcomes also vary: stability is observed with valproate, lamotrigine, rufinamide, cannabidiol, and fenfluramine, whereas medications like levetiracetam, perampanel, brivaracetam, clobazam, and zonisamide can increase aggression or irritability. Nonpharmacological therapies, particularly when they reduce seizure frequency, typically provide greater cognitive and behavioral stability, with some offering improvement. Early intervention-especially through surgical options-appears most beneficial for preserving cognitive function. Additionally, therapies such as the ketogenic diet and neuromodulation may provide independent cognitive benefits beyond seizure control. This review emphasizes the importance of personalized treatment strategies, integrating cognitive and behavioral evaluations in therapy selection. Key components include baseline cognitive and behavioral assessments, followed by regular follow-up evaluations, particularly after therapy changes. Consideration of minimizing ASM polytherapy, careful evaluation of drug-drug interactions, pharmacogenomic implications, and the need for therapeutic drug monitoring in cases of cognitive adverse effects is essential. Future research should focus on developing assessment tools tailored to the unique needs of individuals with LGS, utilizing connectivity measures to assess intervention impacts, and advancing precision therapeutics to improve cognitive and behavioral outcomes.

Pediatric Palliative Epilepsy Surgery: A Report From the Pediatric Epilepsy Research Consortium (PERC) Surgery Database

BACKGROUND

Epilepsy surgery is an underutilized resource for children with drug-resistant epilepsy. Palliative and definitive surgical options can reduce seizure burden and improve quality of life. Palliative epilepsy surgery is often seen as a "last resort" compared to definitive surgical options. We compare patient characteristics between palliative and definitive epilepsy surgical patients and present palliative surgical outcomes from the Pediatric Epilepsy Research Consortium surgical database.

METHODS

The Pediatric Epilepsy Research Consortium Epilepsy Surgery database is a prospective registry of patients aged 0-18 years undergoing evaluation for epilepsy surgery at 20 pediatric epilepsy centers. We included all children with completed surgical therapy characterized as definitive or palliative. Demographics, epilepsy type, age of onset, age at referral, etiology of epilepsy, treatment history, time-to-referral/evaluation, number of failed anti-seizure medications (ASMs), imaging results, type of surgery, and postoperative outcome were acquired.

RESULTS

Six hundred forty patients undergoing epilepsy surgery were identified. Patients undergoing palliative procedures were younger at seizure onset (median: 2.1 vs 4 years, P= 0.0008), failed more ASM trials before referral for presurgical evaluation (P=<0.0001), and had longer duration of epilepsy before referral for surgery (P=<0.0001). During presurgical evaluation, patients undergoing palliative surgery had shorter median duration of video-EEG data collected (P=0.007) but number of cases where ictal data were acquired was similar between groups. The most commonly performed palliative procedure was corpus callosotmy (31%), followed by lobectomy (21%) and neuromodulation (82% responsive neurostimulation vs 18% deep brain stimulation). Palliative patients were further categorized into traditionally palliative procedures vs traditionally definitive procedures. The majority of palliative patients had 50% reduction or better in seizure burden. Seizure free outcomes were significantly higher among those with traditional definitive surgeries, 41% (95% confidence interval: 26% to 57%) compared with traditional palliative surgeries and 9% (95% confidence interval: 2% to 17%). Rate of seizure freedom was 46% at 24 months or greater of follow-up in the traditional definitive group.

CONCLUSIONS

Patients receiving palliative epilepsy surgery trialed more ASMs, were referred later after becoming drug resistant, and had longer gaps between drug resistance and epilepsy surgery compared with patients undergoing definitive epilepsy surgery. The extent of surgical evaluation is impacted if surgery is thought to be palliative. A majority of palliative surgery patients achieved >50% seizure reduction at follow-up, both in groups that received traditionally palliative and traditionally definitive surgical procedures. Palliative surgical patients can achieve greater seizure control and should be referred to an epilepsy surgery center promptly after failing two appropriate anti-seizure medications.

Parents' and children's decision-making and experiences in pediatric epilepsy surgery

BACKGROUND

In pediatric epilepsy surgery, little research has been conducted on parents' decision-making for or against surgery, their satisfaction with the surgical outcome, as well as their children's personal experiences with the process.

OBJECTIVE

This study explores (1) factors that may influence parents' decision-making, (2) factors associated with their postoperative satisfaction, and (3) their children's involvement in decision-making and their experiences with epilepsy surgery.

METHODS

Self-developed questionnaires were provided to parents and their children in Germany, Switzerland, and Austria. Clinical and psychosocial differences between parents who decided for or against surgery, as well as associations between postoperative factors and the parents' satisfaction were statistically analyzed.

RESULTS

Fifty-one questionnaires (42 parent and nine patient questionnaires) were evaluated. Parents who decided for epilepsy surgery reported significantly more frequently to have received a good medical consultation and a consistent recommendation. They made significantly less use of information websites, internet forums, and patient organizations. Their children were classified as more intelligent and resisted surgery less. Most of the parents were satisfied with the surgical outcome (83%). Parents were significantly more satisfied when their children had fewer medication side effects, their memory or concentration had improved, their character or behavior had changed in a positive direction, or when their children were more independent or less excluded. They were also significantly more content when they had more free time to themselves and their professional situation or their relationship with their children, friends, or other family members had improved. However, no significant association was found between parental satisfaction and reduced number of medications or improved seizure outcome. Although the children were reported to have been minimally involved in the decision-making process, they were satisfied with their involvement.

CONCLUSIONS

A good medical consultation that involves the children and considers the family's living conditions is a crucial factor for parents' decision-making on pediatric epilepsy surgery. For parents' satisfaction, a positive change in their child's character or behavior and an improved psychosocial situation of the family are more important than postoperative seizure frequency or number of antiepileptic drugs (AEDs). Therefore, the medical consultation should not only focus on clinical factors, but also point out psychosocial and behavioral changes that may occur after the surgical treatment.

Resective surgery combined with corpus callosotomy for children with non-focal lesional Lennox-Gastaut syndrome

BACKGROUND

The first prospective trial for resective surgery combined with corpus callosotomy (CCT) was performed to investigate the outcomes of the combined surgery in children with Lennox-Gastaut syndrome (LGS) without focal lesion on brain MRI.

METHODS

This study enrolled 68 children with LGS and without focal lesion on brain MRI, of which 25 received medicine (medicine group) and 43 underwent surgery (surgery group), including 20 with exclusively resective surgery (exclusively resection subgroup) and 23 with resective surgery combined with CCT (combined CCT subgroup). All patients were followed for 3-5 years.

RESULTS

Significant differences in seizure control were observed between the medicine group and the exclusively resection subgroup and combined CCT subgroup at the 1-year, 3-year, and 5-year follow-ups. There was a trend that the children with resection combined with CCT had better seizure control than those with exclusively resection at the three follow-ups, but this could not be verified by the statistical method used. Furthermore, significant differences were not observed in seizure control between children with different MRI findings, age at surgery, or pathology in the surgery group. The percentage of long-term seizure-free did not remain as high as the percentage of early stage seizure-free at 1-year follow-up. However, the children with combined CCT surgery demonstrated more postoperative improvement than the children with resective surgery alone based on the mean QOL score (10.78 vs. 5.75, p = 0.0152) and full-scale IQ (7.91 vs. 4.55, p = 0.0446).

CONCLUSIONS

Resective surgery combined with CCT can provide favorable seizure control and obvious improvements in QOL and IQ in children with LGS. This combined approach can be performed in carefully selected LGS children without focal lesions and can localize the epileptogenic zone following a comprehensive preoperative evaluation.

Conceptualizing lennox-gastaut syndrome as a secondary network epilepsy

Lennox–Gastaut Syndrome (LGS) is a category of severe, disabling epilepsy, characterized by frequent, treatment-resistant seizures, and cognitive impairment. Electroencephalography (EEG) shows characteristic generalized epileptic activity that is similar in those with lesional, genetic, or unknown causes, suggesting a common underlying mechanism. The condition typically begins in young children, leaving many severely disabled with recurring seizures throughout their adult life. Scalp EEG of the tonic seizures of LGS is characterized by a diffuse high-voltage slow transient evolving into generalized low-voltage fast activity, likely reflecting sustained fast neuronal firing over a wide cortical area. The typical interictal discharges (runs of slow spike-and-wave and bursts of generalized paroxysmal fast activity) also have a “generalized” electrical field, suggesting widespread cortical involvement. Recent brain mapping studies have begun to reveal which cortical and subcortical regions are active during these “generalized” discharges. In this critical review, we examine findings from neuroimaging studies of LGS and place these in the context of the electrical and clinical features of the syndrome. We suggest that LGS can be conceptualized as “secondary network epilepsy,” where the epileptic activity is expressed through large-scale brain networks, particularly the attention and default-mode networks. Cortical lesions, when present, appear to chronically interact with these networks to produce network instability rather than triggering each individual epileptic discharge. LGS can be considered as “secondary” network epilepsy because the epileptic manifestations of the disorder reflect the networks being driven, rather than the specific initiating process. In this review, we begin with a summation of the clinical manifestations of LGS and what this has revealed about the underlying etiology of the condition. We then undertake a systematic review of the functional neuroimaging literature in LGS, which leads us to conclude that LGS can best be conceptualized as “secondary network epilepsy.”