Preliminary analysis of the effect of vagus nerve stimulation in the treatment of children with intractable epilepsy

BACKGROUND: Implant vagus nerve stimulation is an adjunctive treatment for intractable epilepsy when patients are not suitable for resective surgery. AIM: To identify the safety and efficacy of vagus nerve stimulation in children with intractable epilepsy and analyze the effects on different epilepsy syndromes. METHODS: Eligible children with intractable epilepsy were admitted to the study. We collected data from preoperative assessments as the baseline. During the follow-up time, we recorded the process of seizures (frequency, duration, and seizure type), the changes of drugs or parameters, the complications, etc. The mean reduction rate of seizures, response rate, and McHugh scale were chosen as the outcomes. RESULTS: A total of 213 patients were implanted with Tsinghua Pins vagus nerve stimulators, and the average age was 6.6 years. In the follow-up time of postoperative 3 mo, 6 mo, 12 mo, 18 mo, and 24 mo, the average reduction rate was 30.2%, 49.5%, 56.3%, 59.4%, and 63.2%, while the response rate was 21.8%, 62.5%, 57.1%, 69.2%, and 70.7%. In addition, implanted vagus nerve stimulation had different effects on epilepsy syndromes. The reduction rate of West syndrome increased from 36.4% (postoperative 6 m) to 74.3% (postoperative 24 m). The reduction rate of Lennox-Gastaut syndrome improved from 25.4% to 73.1% in 24 mo. The chi-square test of the five efficacy grades showed P < 0.05. The comparison between the 3-mo follow-up and the 6-mo follow-up showed P < 0.05, and the comparison between the 6-mo follow-up and the 24-mo follow-up showed P > 0.05. CONCLUSION: Vagus nerve stimulation is safe and effective in children with intractable epilepsy, and the seizure reduction occurred in a time-dependent manner. Moreover, patients with West syndrome may get the most benefits.