The efficacy of vagal nerve stimulation in children with pharmacoresistant epilepsy: Practical experience at a Turkish tertiary referral center

Background: Vagus nerve stimulation (VNS) is an effective therapy for pharmacoresistant epilepsy. Nevertheless, information regarding the long-term outcome of VNS in children is limited. Aim: To describe the long-term outcome of VNS in patients with pharmacoresistant epilepsy treated at the Gazi University Medical Faculty Epilepsy Center, Turkey. Patients and methods: The study included 24 patients - all younger than 18 years of age (mean age: 14.31 years). Median age at the time of VNS device implantation was 11 years. Median age at onset of epilepsy was 21 months and median duration of epilepsy was 126 months. All the patients' seizures were intractable with antiepileptic drug treatment and all had been treated with an average of 6 2 antiepileptic medications. In all, 12 patients had secondary generalized seizures and 12 had partial seizures. Because this was a retrospective open study, the number of seizures could not be enumerated in most of these cases. Results: The only factor that was associated with seizure reduction was duration of follow-up. Age at seizure onset and age at VNS device implantation were not associated with seizure reduction. The difference in seizure reduction between patients >12 years of age and patients <12 years of age was not significant. Mean percentage of seizure reduction after 6 months-7 years of treatment was, respectively, 22.5% (n = 24) (6th month), 32% (n = 20) (1st year), 42% (n = 16) (2nd year), 50.45% (n = 11) (3rd year), 52% (n = 10) (4th year), 60% (n = 8) (5th year), 61.25% (n = 8) (6th year), and 61.6% (n = 6) (7th year). The positive effect of VNS persisted throughout the follow-up period. Conclusions: Although it is an expensive method, VNS is an effective treatment method. This series shows the necessity of long-term follow-up series for understanding the efficacy and advantages of VNS. Prospective, long-term double-blind studies with large samples are needed to confirm the present study's findings. (C) 2009 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.