Utility of repeat stereotactic EEG in pediatric patients with tuberous sclerosis.

objectiveTuberous sclerosis complex (TSC) is a rare genetic disorder associated with early-onset drug-resistant epilepsy (DRE) secondary to intracranial tubers. Many patients undergo stereo-EEG (sEEG) for seizure onset localization, sometimes requiring multiple sEEGs and subsequent epilepsy surgeries. Our objective was to evaluate the effects of single versus multiple sEEGs on seizure outcomes in pediatric patients with TSC-associated DRE.

methodsRetrospective review of 45 pediatric TSC patients who underwent epilepsy surgery at our institution (2/2013-4/2026). Collected data included demographics, seizure history, number of sEEGs, surgical interventions, and outcomes. Primary outcomes were Engel scores after definitive epilepsy surgery.

resultsAmong 34 identified TSC patients who underwent sEEG prior to surgery, 19 had one sEEG, 15 had two or more (mean ± SE: 2.4 ± 0.2, range: 2-5). 68% of single sEEG patients had one presumed seizure focus on phase I vEEG versus only 27% of multiple sEEG patients (p = 0.03). Phase I vEEG and MEG data were concordant in 67% of single sEEG patients and 91% of multiple sEEG patients. Single ictal focus epilepsy on vEEG was significantly associated with use of only single sEEG on logistic regression (p = 0.01). Patients with a single sEEG more often underwent laser ablation (53% vs. 27%), while those with multiple sEEGs more commonly underwent resective surgery (73% vs. 47%, p = 0.171). Four patients (20%) in the single sEEG group had additional treatment surgeries without repeat sEEG. At one-year and most recent (2.3 ± 0.4 vs. 2.8 ± 0.4 years) follow-up in patients who had at least 1 year of follow up after their most recent surgery (n = 24, 82%), favorable seizure outcomes (Engel I/II) were observed in 86% and 93% in single sEEG patients, and 64% and 79% in multiple sEEG patients (p > 0.99). SIGNIFICANCE: TSC-associated DRE is often multifocal and challenging to treat, requiring sEEG for localization. Presurgical multifocal vEEG or MEG findings may predict need for repeat sEEG. While multifocal networks may necessitate additional sEEG evaluations and subsequent surgeries, favorable seizure outcomes can be achieved. PLAIN LANGUAGE SUMMARY: Tuberous sclerosis complex (TSC) is a rare genetic condition that often causes difficult-to-control epilepsy in children. Some patients need a procedure called stereo-EEG (sEEG) to locate where seizures begin in the brain before surgery. We reviewed 34 children with TSC who underwent sEEG before epilepsy surgery. Children with a single seizure focus were more likely to need only one sEEG, while those with multiple seizure areas often required repeat sEEGs and additional surgeries. Despite more complex epilepsy, many patients still achieved good seizure control after treatment. These findings suggest that repeat sEEGs may help guide effective treatment in children with multifocal epilepsy.