Vagus nerve stimulation for children with treatment-resistant epilepsy: a consecutive series of 141 cases

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>The authors undertook this study to analyze the efficacy of vagus nerve stimulation (VNS) in a large consecutive series of children 18 years of age and younger with treatment-resistant epilepsy and compare the safety and efficacy in children under 12 years of age with the outcomes in older children.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>The authors retrospectively reviewed 141 consecutive cases involving children (75 girls and 66 boys) with treatment-resistant epilepsy in whom primary VNS implantation was performed by the senior author between November 1997 and April 2008 and who had at least 1 year of follow-up since implantation. The patients' mean age at vagus nerve stimulator insertion was 11.1 years (range 1–18 years). Eighty-six children (61.0%) were younger than 12 years at time of VNS insertion (which constitutes off-label usage of this device).</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Follow-up was complete for 91.8% of patients and the mean duration of VNS therapy in these patients was 5.2 years (range 25 days–11.4 years). Seizure frequency significantly improved with VNS therapy (mean reduction 58.9%, p &lt; 0.0001) without a significant reduction in antiepileptic medication burden (median number of antiepileptic drugs taken 3, unchanged). Reduction in seizure frequency of at least 50% occurred in 64.8% of patients and 41.4% of patients experienced at least a 75% reduction. Major (3) and minor (6) complications occurred in 9 patients (6.4%) and included 1 deep infection requiring device removal, 1 pneumothorax, 2 superficial infections treated with antibiotics, 1 seroma/hematoma treated with aspiration, persistent cough in 1 patient, severe but transient neck pain in 1 patient, and hoarseness in 2 patients. There was no difference in efficacy or complications between children 12 years of age and older (FDA-approved indication) and those younger than 12 years of age (off-label usage). Linear regression analyses did not identify any demographic and clinical variables that predicted response to VNS.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Vagus nerve stimulation is a safe and effective treatment for treatment-resistant epilepsy in young adults and children. Over 50% of patients experienced at least 50% reduction in seizure burden. Children younger than 12 years had a response similar to that of older children with no increase in complications. Given the efficacy of this device and the devastating effects of persistent epilepsy during critical developmental epochs, randomized trials are needed to potentially expand the indications for VNS to include younger children.</jats:p></jats:sec>

Vagal nerve stimulation for the treatment of medically refractory epilepsy: a review of the current literature

“…This volume of information has been used to establish trends in outcome not otherwise evident in investigations with smaller sample sizes. Focal epileptogenic foci and the presence of cortical malformations have been shown to be positive predictors of success with VNS treatment by multiple investigators, including Elliott et al, 10,11 Janszky et al, 19 and Ghaemi et al, 15 but the issue of most appropriate age of implantation appears to remain subject to argument. Ghaemi et al found younger age at initiation of treatment to be a positive predictor, whereas both Elliott et al and Murphy et al found no statistical correlation between younger age and positive outcome.…”

“…There were 14 publications that used this standard, and of the 1378 patients studied, a mean of 50.9% (range 18.4%-67%) showed a 50% or greater decrease in seizure frequency. 1,2,4,5,[8][9][10][11]15,[24][25][26][27][28] Five of the remaining studies used the mean or median frequency reduction from baseline. 3,14,17,22,23 The mean seizure reduction in these investigations was 42.8% (range 28%-66%).…”

“…In the 2 largest pediatric investigations, Elliott et al 11 and Murphy et al 24 studied 141 and 96 children, respectively. Both demonstrated a significant number of responders (≥ 50% seizure reduction) with 64.8% and 45%, respectively; however, Elliott et al, having greater statistical power, were able to demonstrate significance at p < 0.0001 in mean reduction of episodes at 58.9%.…”

Non-pharmacologic Therapeutic Alternatives for Children with Pharmacoresistant Epilepsy: Vagus Nerve Stimulation and Ketogenic Diet

“…Rezektif cerrahiye aday olmayan ve ilaca dirençli fokal (sekonder jeneralizasyon olsun ya da olmasın) veya jeneralize nöbetleri devam eden çocuklarda nöbet sıklığını azaltmaya yönelik ek tedavi olarak endikedir. [1,2,[4][5][6] Amerikan gıda ve ilaç kurumu (FDA) 1997 yılında 12 yaş üzeri çocuklar için ek tedavi olarak VSS'yi uygun görmüştür. O zamandan günümüze yapılan çalışma-ların çoğu, VSS'nin klinik etkinliğini erişkin hastalarda değerlendirmiştir.…”

The role of vagus nerve stimulation in refractory epilepsy

“…When comparing patients younger and older than 12 years, no significant difference in efficacy or complication rate was demonstrated after five years of follow-up in 141 patients 39 , although some reported increased infection rates in children 40 . Predictors of response have not been completely clarified, although some elements may have a prognostic value.…”