Safety and efficacy of responsive neurostimulation in the pediatric population: Evidence from institutional review and patient-level meta-analysis

Background: Responsive neurostimulation (RNS) is a novel technology for drug-resistant epilepsy rising from bilateral hemispheres or eloquent cortex. Although recently approved for adults, its safety and efficacy for pediatric patients is under investigation. Methods: A comprehensive literature search (Pubmed/Medline, Scopus, Cochrane) was conducted for studies on RNS for pediatric epilepsy (<18 y/o) and supplemented by our institutional series (4 cases). Reduction in seizure frequency at last follow-up compared to preoperative baseline comprised the primary endpoint. Results: A total of 8 studies (49 patients) were analyzed. Median age at implant was 15 years (interquartile range [IQR] 12–17) and 63% were males. A lesional MRI was noted in 64% (14/22). Prior invasive EEG recording was performed in the majority of patients (90%) and the most common modality was stereoelectroencephalography (57%). The most common implant location (total of 94 RNS leads) was the frontal lobe (27%), followed by mesial temporal structures (23%) and thalamus (17%). At a median follow-up of 22 months, median seizure frequency reduction was 75% (IQR: 50–88%) and 80% were responders (>50% seizure reduction). Responses ranged from 50% for temporal lobe epilepsy to 81–93% for frontal, parietal, and multilobar epilepsy. Four infections were observed (8%) and there were no hematomas or postoperative neurological deficits. Conclusion: Current evidence, albeit limited by potential publication bias, supports the promising safety and efficacy profile of RNS for medically refractory pediatric epilepsy. Randomized controlled trial data are needed to further establish the role of this intervention in preoperative discussions with patients and their families.