Concurrent brain-responsive and vagus nerve stimulation for treatment of drug-resistant focal epilepsy

Objective: Clinical trials of a brain-responsive neurostimulator, RNS (R) System (RNS), excluded patients with a vagus nerve stimulator, VNS (R) System (VNS). The goal of this study was to evaluate seizure outcomes and safety of concurrent RNS and VNS stimulation in adults with drug-resistant focal-onset seizures.Methods: A retrospective multicenter chart review was performed on all patients with an active VNS and RNS who were treated for a minimum of 6 months with both systems concurrently. Frequency of disabling seizures at baseline before RNS, at 1 year after RNS placement, and at last follow-up were used to calculate the change in seizure frequency after treatment. Data on adverse events and complications related to each device were collected.Results: Sixty-four patients from 10 epilepsy centers met inclusion criteria. All but one patient received RNS after VNS. The median follow-up time after RNS implantation was 28 months. Analysis of the entire population of patients with active VNS and RNS systems revealed a median reduction in seizure frequency at 1 year post-RNS placement of 43% with a responder rate of 49%, and at last follow-up a 64% median reduction with a 67% responder rate. No negative interactions were reported from the concurrent use of VNS and RNS. Stimulation-related side-effects were reported more frequently in association with VNS (30%) than with RNS (2%).Significance: Our findings suggest that concurrent treatment with VNS and RNS is safe and that the addition of RNS to VNS can further reduce seizure frequency.(c) 2022 Elsevier Inc. All rights reserved.

Automated summary

The concurrent treatment with VNS and RNS is safe and adding RNS can further reduce seizure frequency for adults with drug-resistant focal-onset seizures.