Vagus Nerve Stimulation for Intractable Focal Epilepsy

Abstract

Abstract Background Epilepsy is a common neurological condition affecting 0.5-1% of the population. Despite the advances in the medical management of epilepsy 25-35% of patients have poor control of their seizures or have unacceptable side effects from the medication. Aim and Objectives To make up-to-date recommendations for the value of vagus nerve stimulation (VNS) in patients suffering from intractable focal epilepsy and not candidates for surgical resection. Subjects and Methods Eight studies were included in the present meta-analysis. The flow diagram of the study selection processes. The total number of patients in the eight included studies was 266. The follow-up periods ranged from 12–124 months. Because of significant heterogeneity (I2 = 94 %) among the included studies, a sensitivity analysis was performed. Result 59.4% of all the included patients showed a 50% or greater reduction in seizure frequency after VNS. The patients with > 50% reduction in seizure frequency ranged from 25–66% among the eight included studies. Non-significant improvement in seizure frequency after VNS. Conclusion After VNS, the frequency of seizures was reduced by 50% in about 59.4% of the patients with intractable focal seizures. The present study's random effects forest plot, however, indicated that the reduction in seizure frequency following VNS was not statistically significant. The effectiveness of VNS in reducing seizure frequency in the population under study is therefore still unknown,.