Vagus Nerve Stimulation in 16 Children with Refractory Epilepsy

Abstract
Summary: Purpose: Vagus nerve stimulation (VNS) has been reported to produce >90% reduction in the number of seizures in children with intractable epilepsy. These encouraging results need confirmation. Methods: Sixteen children, 10 boys and 6 girls aged 4‐19 years, were treated with VNS (Cyberonics, Webster, TX, U.S.A.) for 12‐24 months. Seizure frequency, seizure severity, changes in quality of life (QOL: visual analogue scale), and side effects were recorded. Eight children had partial and 8 had generalized seizures; 4 of the latter had Lennox‐Gastaut syndrome (LGS). Results: During the tenth to twelfth month of VNS, 6 of 16 children experienced ≥50% reduction in seizure frequency. One girl became seizure‐free. Seizure severity showed an average decrease in the score from 15 to 11. After 10 months of treatment, QOL was estimated to have improved ≥50% in 6 of 16 children. Reduction in seizure frequency, decreased seizure severity, and reported improvement in QOL did not entirely coincide. Six children experienced hoarseness, 1 had neck pain, 2 had hypersalivation, 2 experienced tiredness, 2 had aspiration episodes during liquid intake, and 6 had electrical transmission problems; in 4 the problem has been surgically corrected. Five stimulators were turned off due to lack of efficacy. Conclusions: Six of 16 children with refractory epilepsy treated with VNS improved, with a reduction not only in seizure frequency but also in seizure severity and in QOL.