Curative effect of vagus nerve stimulation on treatment-resistant epilepsy and its parameter modulation

Objective To study the curative effect of vagus nerve stimulation(VNS) on treatment-resistant epilepsy and its parameter modulation.Methods Forty-six treatment-resistant epilepsy patients were treated with VNS 2-3 weeks after operation.Stimulation parameters were adjusted.The output current of generator was gradually increased from 0.25mA to 3.0mA.The stimulation cycle,intermission,frequency and pulse width of the generator were 30s,5min,20-30Hz,and 250-1 000μs,respectively.The patients were followed up for more than 8 months.Results Among the 39 patients who were followed up,McHugh grades I-IV+V were found in 13,11,11 and 4 patients,respectively.Of these patients,4(10.3%) had no seizure after VNS,24(61.5%) had their seizure reduced over 50%.Conclusion VNS is a safe and effective procedure for children and adult patients with treatment-resistant epilepsy and can reduce their seizure over 50%.Its curative effect is correlated with the parameter modulation and stimulation time.