Authors: Elsa Arocho-Quinones, MD; Elsa Arocho-Quinones, MD; Sean Lew, MD; Pediatric Stereotactic Laser Ablation Workgroup (Milwaukee, WI)

Introduction: This study aims to assess the safety and efficacy of magnetic resonance-guided stereotactic laser ablation (SLA) therapy in the treatment of refractory epilepsy in pediatric patients. Methods: Data from 17 North American centers was retrospectively reviewed. Clinical, technical, and radiographic data for pediatric patients treated with SLA for a diagnosis of refractory epilepsy from 2008 to present was collected and analyzed. Results: A total of 195 patients (ages 12.8yr ± 5.9yr) were included. Treatment locations included cortical (51%), subcortical (11%), mesiotemporal (25%), and hypothalamic (13%). The MRI-guided SLA systems utilized were Visualase in 171 cases and Neuroblate in 24 cases. The goals of the procedures were ablation (134), disconnection (48), or both (13). Median follow-up time was 23.7months (range 3-71months). Engel classification was reported for 71.3% patients. Of these patients, 91 (65.5%) had Engel Class I or II, and 48 (34.5%) had Engel Class III or IV at latest follow up. Improvement in targeted seizure type was reported for 82% patients. Subsequent surgery after SLA treatment was not required in 81.5% patients. None of the patients with epilepsy secondary to brain tumors required subsequent surgery after SLA therapy. Complications included: malpositioned catheters (3), intracranial hemorrhage (1), transient neurological deficits (16), permanent neurological deficits (3), worsened neuropsychological testing (1), symptomatic perilesional edema (4), and hydrocephalus (1). Neither the number of laser trajectories or number of lesions created resulted in a significantly increased risk of complications, however, there was an association between higher volumes of the lesion created and the incidence of complications. Conclusion: SLA is an effective minimally invasive treatment option for pediatric patients with refractory epilepsy and brain tumors although not without risks. A larger volume of data will help define the indications and demonstrate the long-term efficacy and safety profile of this technology in the pediatric population.