Vagus nerve stimulation for drug-resistant epilepsy in children and young adults
We present our experience with the use of intermittent vagal nerve stimulation in 13 patients with medically intractable epilepsy. A surgical approach, with the exception of callosotomy, was impossible. The age range was 6-28 years (median 17 years). In all patients the epilepsy was severe and in six of them was symptomatic. Seven patients had Lennox-Gastaut syndrome, one epilepsy with myoclonic-astatic seizures, four localization-related and one symptomatic generalized epilepsy. The length of the follow-up averaged 22 months (range 8 months-3 years). Of the 13 patients, five (38.4%) had a 50% or more reduction in the number of seizures compared with preimplantation. Of these patients, one with a localization-related epilepsy had a 90% reduction as well as a significant improvement in alertness. Three patients showed no improvement with regard to the number of seizures but there was an improvement in alertness and, in one case in hyperactivity. Some seizure types responded better than others did: complex partial seizures with secondary generalization and atonic seizures. All our responsive patients improved in the first 2 months of VNS activation and only one case with further improvement was observed after this period. Considering the severity of the epilepsy the results can be considered satisfactory. We think that this treatment appears to be a safe adjunctive therapy for children and adults with medically and surgically intractable epilepsy.