Vagal nerve stimulation for pharmacoresistant epilepsy in children

Department of Neurosurgery, Intellectual and Developmental Disabilities Research Center, Mattel Children's Hospital, David Geffen School of Medicine, University of California, Los Angeles, California, 90095, USA.
Surgical Neurology International (Impact Factor: 1.18). 10/2012; 3(Suppl 4):S269-74. DOI: 10.4103/2152-7806.103017
Source: PubMed

ABSTRACT Vagus nerve stimulation (VNS) is an adjunctive treatment for adult patients with pharmacoresistant epilepsy. Little is known about VNS therapy for children with epilepsy. This article will: (1) Review the contemporary medical literature related to VNS therapy in children with epilepsy, (2) describe the experience of VNS treatment in 153 children less than 18 years of age, in the University of California, Los Angeles (UCLA) Pediatric Epilepsy Surgery Program, from 1998 to 2012, and (3) describe the surgical technique used for VNS implantation at UCLA. Review of the literature finds that despite different etiologies and epilepsy syndromes in children, VNS appears to show a similar profile of efficacy for seizure control compared to adults, and low morbidity and mortality. The UCLA experience is similar to that reported in the literature for children. VNS constitutes about 21% of our pediatric epilepsy surgery volume. We have implanted VNS in infants as young as six months of age and the most common etiology is the Lennox-Gastaut Syndrome. About 5% of the patients are seizure-free with VNS therapy and there is a low rate of surgically related complications. The UCLA surgical approach emphasizes minimal direct manipulation of the vagus nerve and adequate wire loops, to prevent a lead fracture. In summary, VNS is a viable palliative treatment for medically refractory epilepsy in children, with outcomes and complications equal to adult patients. Being a small child is not a contraindication for VNS therapy, if needed for refractory epilepsy.

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    ABSTRACT: Vagus nerve stimulation (VNS) seems to be effective in the management of selected cases of pharmacoresistant epilepsy in children. This was a case-control prospective study of children with refractory epilepsy submitted to vagal nerve stimulator implantation and a control group with epilepsy treated with antiepileptic drugs. Patients under 18years of age who underwent clinical or surgical treatment because of pharmacoresistant epilepsy from January 2009 to January 2012 were followed and compared with an age-matched control group at final evaluation. Statistically significant differences were observed considering age at epilepsy onset (VNS group - 1.33±1.45years; controls - 3.23±3.11; p=0.0001), abnormal findings in neurological examination (p=0.01), history of previous ineffective epilepsy surgery (p=0.03), and baseline seizure frequency (p=0.0001). At long-term follow-up, 55.4% of the patients in the VNS group had at least 50% reduction of seizure frequency, with 11.1% of the patients presenting 95% reduction on seizure frequency. Also, a decrease in traumas and hospitalization due to seizures and a subjective improvement in mood and alertness were observed. The control group did not show a significant modification in seizure frequency during the study. In this series, VNS patients evolved with a statistically significant reduction of the number of seizures, a decreased morbidity of the seizures, and the number of days in inpatient care. In accordance with the current literature, VNS has been proven to be an effective alternative in the treatment of pediatric patients with drug-resistant epilepsy.
    Epilepsy & Behavior 11/2013; 31. DOI:10.1016/j.yebeh.2013.10.011 · 2.06 Impact Factor
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    ABSTRACT: Refractory epilepsy is a common disorder both in humans and dogs and treatment protocols are difficult to optimise. In humans, different non-pharmacological treatment modalities currently available include surgery, the ketogenic diet and neurostimulation. Surgery leads to freedom from seizures in 50-75% of patients, but requires strict patient selection. The ketogenic diet is indicated in severe childhood epilepsies, but efficacy is limited and long-term compliance can be problematic. In the past decade, various types of neurostimulation have emerged as promising treatment modalities for humans with refractory epilepsy. Currently, none of these treatment options are used in routine daily clinical practice to treat dogs with the condition. Since many dogs with poorly controlled seizures do not survive, the search for alternative treatment options for canine refractory epilepsy should be prioritised. This review provides an overview of non-pharmacological treatment options for human refractory epilepsy. The current knowledge and limitations of these treatments in canine refractory epilepsy is also discussed.
    The Veterinary Journal 10/2013; DOI:10.1016/j.tvjl.2013.09.055 · 2.17 Impact Factor
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    ABSTRACT: Objective To gain insight into the long-term impact of vagus nerve stimulation (with VNS Therapy) in children with drug-resistant epilepsy, we conducted the largest retrospective multicenter study to date over an extended follow-up period of up to 24months. Methods The primary objective was to assess change in seizure frequency of the predominant seizure type (defined as the most disabling seizure) following VNS device implantation. Treating physicians collected data from patient records from baseline to 6, 12, and 24months of follow-up. ResultsThe analysis population included 347children (aged 6months to 17.9years at the time of implant). At 6, 12, and 24months after implantation, 32.5%, 37.6%, and 43.8%, respectively, of patients had 50%reduction in baseline seizure frequency of the predominant seizure type. The responder rate was higher in a subgroup of patients who had no change in antiepileptic drugs (AEDs) during the study. Favorable results were also evident for all secondary outcome measures including changes in seizure duration, ictal severity, postictal severity, quality of life, clinical global impression of improvement, and safety. Post hoc analyses demonstrated a statistically significant correlation between VNS total charge delivered per day and an increase in response rate. VNS Therapy is indicated as adjunctive therapy in children with focal, structural epilepsies, who for any reason are not good candidates for surgical treatment following the trial of two or more AEDs. Children with predominantly generalized seizures from genetic, structural epilepsies, like Dravet syndrome or Lennox-Gastaut syndrome, could also benefit from VNS Therapy. SignificanceThe results demonstrate that adjunctive VNS Therapy in children with drug-resistant epilepsy reduces seizure frequency and is well tolerated over a 2-year follow-up period. No new safety issues were identified. A post hoc analysis revealed a dose-response correlation for VNS in patients with epilepsy.
    Epilepsia 09/2014; 55(10). DOI:10.1111/epi.12762 · 4.58 Impact Factor