Vagus nerve stimulation in pharmacoresistant epilepsy of childhood and adolescence

Since five years the vagus nerve stimulation therapy (VNS) is used in Germany, Austria and Switzerland for the treatment of pharmacoresistant epilepsy of childhood and adolescence. About 300 children were implanted with the VNS device, nearly 200 patients were followed using an open, not randomized, prospective protocol up to 24 months. Mainly mentally retarded children with a psychomotor retardation suffering from a catasrophic epilepsy are candidates for the VNS, if epilepsy surgery is not possible. It was shown, that 50 percent of these patients improved with this adjunctive, palliative and non pharmacological, antiepileptic therapy in terms of at least 50% seizure reduction. Less than 6% of patients became seizure free. Subgroups with Lennox-Gastaut syndrome and patients with previous unsuccessful epilepsy surgery presented with similar seizure reduction rates as the entire cohort. Patients with an early onset of epilepsy before the age of 12 months seemed to benefit more often compared to patients with later seizure onset. Also patients without significant seizure reduction showed improvements of quality of life concerning vigilance and mood. Recent EEG findings revealed differences in responders versus nonresponders concerning frequencies of the delta, alpha and beta band as well as very slow cortical potentials.