Vagal nerve stimulation—the Norwegian experience

The purpose of this open retrospective study was to analyze the efficacy and tolerability of vagal nerve stimulation (VNS) in a Norwegian cohort of referral patients with refractory epileptic seizures. A total of 47 patients have been assessed after a mean follow-up time of 2.7 years. Mean age was 34.4 years, mean duration of epilepsy was 25.3 years. Forty-two patients (89%) had localization-related epilepsy, 36 patients (77%) had daily seizures. The patients had tried on average 9.5 antiepileptic drugs, and 12 patients (26%) had undergone epilepsy surgery. Sixteen patients (34%) had >50% reduction of seizure frequency with VNS, of which one patient became seizure free. The stimulation was generally well tolerated, but three patients requested the device removed because of troublesome side effects. We conclude that VNS is an efficacious and safe mode of treatment that should be offered to patients with medically and surgically refractory seizures.