Real-World Preliminary Experience With Responsive Neurostimulation in Pediatric Epilepsy: A Multicenter Retrospective Observational Study

Abstract

Background: Despite the well-documented utility of responsive neurostimulation (RNS, NeuroPace) in adult epilepsy patients, literature on the use of RNS in children is limited.

Objective: To determine the real-world efficacy and safety of RNS in pediatric epilepsy patients.

Methods: Patients with childhood-onset drug-resistant epilepsy treated with RNS were retrospectively identified at 5 pediatric centers. Reduction of disabling seizures and complications were evaluated for children (<18 yr) and young adults (>18 yr) and compared with prior literature pertaining to adult patients.

Results: Of 35 patients identified, 17 were <18 yr at the time of RNS implantation, including a 3-yr-old patient. Four patients (11%) had concurrent resection. Three complications, requiring additional surgical interventions, were noted in young adults (2 infections [6%] and 1 lead fracture [3%]). No complications were noted in children. Among the 32 patients with continued therapy, 2 (6%) achieved seizure freedom, 4 (13%) achieved ≥90% seizure reduction, 13 (41%) had ≥50% reduction, 8 (25%) had <50% reduction, and 5 (16%) experienced no improvement. The average follow-up duration was 1.7 yr (median 1.8 yr, range 0.3-4.8 yr). There was no statistically significant difference for seizure reduction and complications between children and young adults in our cohort or between our cohort and the adult literature.

Conclusion: These preliminary data suggest that RNS is well tolerated and an effective off-label surgical treatment of drug-resistant epilepsy in carefully selected pediatric patients as young as 3 yr of age. Data regarding long-term efficacy and safety in children will be critical to optimize patient selection.

Keywords: Brain stimulation; Children; Closed-loop; Eloquent cortex; Multifocal epilepsy; Neuromodulation.

Graphical Abstract

FIGURE 1.

Patient flow chart. A total of 35 patients underwent RNS (NeuroPace) implantation in this series. The outcome of RNS therapy was assessed for 32 patients who received RNS therapy, excluding 2 patients with wound infection requiring RNS removal and 1 patient who achieved seizure freedom without RNS therapy. The outcome for a patient who initially received RNS therapy but subsequently underwent RNS removal and hippocampectomy due to a lead fracture was assessed at the time of the most recent follow-up before the RNS removal.

FIGURE 2.

A-C, RNS (NeuroPace) placement in a 3-yr-old patient with multifocal seizure foci. The patient, who had been noted to have seizure foci involving the right insula and left inferior frontal area, underwent uncomplicated RNS placement with 2 depth leads targeting those areas. A, Lateral and B, anterior-posterior postoperative X-ray films show appropriate placement of the RNS device. C, Coronal postoperative CT demonstrated appropriate placement of the RNS neurostimulator device along the contour of the left parietal area.