Vagus nerve stimulation for children and adolescents with intractable epilepsies

Background: Vagus nerve stimulation (VNS) has been shown to be efficacious in the treatment of patients > 12 years of age with refractory partial epil epsies and it is suggested that VNS should be considered as one of the trea tment options for these patients. Methods: Four patients had partial epilepsies and one had symptomatic gener alized epilepsy. After observation of the baseline seizure frequency and th e average seizure frequency for 3 months, the VNS system was implanted. The reafter, seizure frequency, average seizure frequency of each seizure type during the month just before the evaluation, seizure severity, side effects and quality of life were recorded. Results: In four of five patients, overall seizure frequency was reduced > 50% after VNS treatment. The seizure types that showed a > 50% reduction in frequency were auras, focal clonic, generalized tonic clonic seizures, ast atic, versive, hypomotor, generalized tonic and generalized clonic seizures according to Luders' classification. In two patients, as major convulsive seizures were reduced in number after VNS treatment, dialeptic seizures (no n-convulsive seizure with lapse of consciousness) gradually appeared. In on e patient without significant seizure reduction, quick recovery from postic tal periods after generalized tonic seizure was seen after treatment. In on e patient with generalized epilepsy, improvement of cognitive function was reported by his guardians. After VNS, the number of antiepileptic drugs was reduced from three to one in one patient. No significant adverse effects w ere noted in any patients. Conclusions: Our results suggest that VNS is well tolerated in young patien ts with intractable epilepsies and it may be an important non-pharmacologic treatment option for children with severe epilepsies who cannot tolerate m edical therapy and/or are not candidates for epilepsy surgery.