Impact of Previous Surgery on Success of Magnetic Resonance-guided Laser Interstitial Thermal Therapy (MRgLITT) to Treat Pediatric Epilepsy: An Institutional Experience

Abstract

There is an emerging role for minimally invasive magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) in the treatment of pediatric epilepsy refractory to medication. To date, predictors of MRgLITT success have not been established in a sizeable singular experience. Correspondingly the aim of this study was to elucidate if previous surgical history predicts MRgLITT success in this setting. A retrospective review was conducted of our MRgLITT procedures for pediatric (aged <19 years) epilepsy from 2011-2020 with documented seizure outcomes at 1- and 2-years after procedure. Categorical and continuous data were compared using Chi-squared and student's t-test respectively. A total of 41 patients satisfied all criteria with 16 (39%) females and 25 (61%) males. Following MRgLITT, seizure-freedom at 1-year was achieved in 15 (37%) patients. In the cohort, there were 14 (34%) patients who had undergone previous open surgery for epilepsy at mean age of 9.4 ± 5.5 years. Patients with a previous open surgery history were found to statistically experience longer length of hospitalization after MRgLITT (P=0.04) with a statistically lower proportion of seizure-freedom at 1-year after MRgLITT (14% vs 48%, P=0.03). However, there was no difference in the rate of seizure-freedom at 2-years (29% vs 41%, P=0.44), as well as no difference in subsequent surgical interventions for seizure management between groups. Based on our institutional experience, patients with previous open surgery history may experience longer length of hospitalization after MRgLITT for pediatric epilepsy and lesser response in seizure-freedom within the first year but with non-inferior seizure-freedom by the second year.