Vagus nerve stimulator placement tied to post operative seizure freedom in children 6 years old or younger
VNS implantation for patients younger than 4 years of age with generalized onset MRE has not been approved by the FDA. This retrospective study establishes feasibility, illustrates an acceptable safety profile in children younger than 6 years, and demonstrates efficacy comparable to that reported in older patients.
Vagus nerve stimulation is an established, effective treatment for medically refractory epilepsy (MRE). In adults, reduction or elimination of seizures occurs in 65%–70% of patients who are implanted with a vagus nerve stimulator (VNS) after stimulation parameters are optimized. Other observed improvements in adults have included improved alertness (58%–63%), mood (45%), and memory (30%–38%).
Vagus nerve stimulation has similarly been used effectively in children. Multiple single-institution, noncontrolled, observational pediatric studies have demonstrated its effectiveness against a wide range of seizure semiologies. Additional benefits include greater alertness and responsiveness and increased overall school performance (29%–39%). Complications have been observed in 3%–11% of patients but are generally self-limited or minor.
Food and Drug Administration (FDA) approval for VNS placement in populations younger than 12 years, however, took 20 years after the initial approval of vagus nerve stimulation. In 1997, vagus nerve stimulation was only approved for adult and pediatric patients older than age 12 years with MRE. In 2017, the FDA extended the use of the LivaNova VNS system to patients older than 4 years with partial-onset seizures that were also medically refractory. Severe generalized seizures, however, are common in young childhood, and vagus nerve stimulation has demonstrated effectiveness and safety in limited, uncontrolled case series.
The study by Maleknia et al published in Journal of Neurosurgery Paediatrics,evaluates a large cohort of children younger than 6 years of age with a mean follow-up > 8 years. The study is the first review of VNS placement in children 6 years and younger with a mean follow-up > 8 years. Despite the longer-term follow-up, their study demonstrates ≥ 50% reduction in seizures. This is in accordance with the seizure reduction rates seen in prior literature with older patients.
There is a promising double-blind randomized controlled trial underway in China to evaluate the differences in efficacy and safety with versus without VNS treatment in children between the ages of 3 and 6 years with MRE. Like the current study, this trial will test the age range currently accepted for VNS placement.
“Based on our patient cohort, VNS placement in young children can be efficacious and safe for treatment of MRE. Vagus nerve stimulation can and should be used as an adjunctive therapy for children with MRE to reduce seizure frequency over a 5-year time span,” conclude the authors.
Reference
Postoperative seizure freedom after vagus nerve stimulator placement in children 6 years of age and younger
Pedram Maleknia MBA, Timothy D. McWilliams BA, Ariana Barkley MD, Dagoberto Estevez-Ordonez MD, Curtis Rozzelle MD, and Jeffrey P. Blount MD, MPH
J Neurosurg Pediatr 31:329–332, 2023
DOI link: https://doi.org/10.3171/2022.12.PEDS22302
