Vagus nerve stimulation: effectiveness and tolerability in 64 paediatric patients with refractory epilepsies

Abstract

We discuss the effectiveness, tolerability, and safety of vagus nerve stimulation (VNS) as adjunctive therapy in 64 paediatric patients with refractory epilepsies. Materials and methods. Sixty-four patients (34 male and 30 female) implanted with VNS for refractory epilepsy were analysed. Electroclinical features were compatible with Lennox-Gastaut syndrome in 46 patients, focal epilepsies in 10 patients, Dravet syndrome in three patients, epilepsy with myoclonic-astatic seizures in three patients, and West syndrome in two. The NeuroCybernetic Prosthesis (NCP) system (Cyberonics, Webster, TX, USA) was employed and the following stimulation parameters were used: output current of 1 to 2.5mA, signal frequency of 30Hz, signal pulse width of 500s, and signal "on" and "off" times of 30 seconds and 5 minutes, respectively. Results. Of 46 patients with LGS, 30 cases showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. Ten patients with focal epilepsy, three patients with myoclonic-astatic seizures, two patients with Dravet, and two patients with West showed a significant improvement in seizure control, with a reduction in seizure frequency of at least 50%. A good clinical response was evident early and efficacy progressively improved with the duration of treatment up to 36 months. In a significant number of patients, reduced seizure severity and shorter recovery time and hospital stay were also observed. VNS was well tolerated in all patients. Conclusion. VNS is an effective and well-tolerated treatment for paediatric patients with refractory epilepsies, improving quality of life and neuropsychological performance.

A Prospective Long-Term Study on the Outcome After Vagus Nerve Stimulation at Maximally Tolerated Current Intensity in a Cohort of Children With Refractory Secondary Generalized Epilepsy

“…Additionally, some studies classified VNS outcome using Engel's scale, which is clearly unsuitable for the rating of palliative procedures since patients would all cluster around Engel's III rating. There was suggestion in the literature that there might be a progressive improvement on seizure control over the years during VNS . In the present and other series , the results after one year of VNS were statistically similar to that obtained after two years, suggesting that we could reliably forecast the final outcome after one year of VNS.…”

Treatment of infantile spasms

“…With respect to surgical neurostimulation modalities, such as vagus nerve stimulation (VNS), there is speculation that functional modulation of brainstem and thalamic targets may effectively desynchronize the widespread cortical networks that mediate IS and hypsarrhythmia. However, although children with IS have been included in several series evaluating the efficacy of VNS among young children with epilepsy, IS‐specific outcomes have been reported in only one study and were rather modest, without mention of any impact on hypsarrhythmia . In my own center's experience with VNS in the treatment of 19 highly refractory children with IS, we have observed only one case with prompt resolution of both ES and hypsarrhythmia.…”

Efficacy and tolerability of the ketogenic diet in Dravet syndrome – Comparison with various standard antiepileptic drug regimen

“…There are only limited data on Vagus-Nerve-Stimulation (VNS) in DS. However, good efficacy and only mild short and long term side effects were reported from small case series (Cersosimo et al, 2011;Spatola et al, 2013;Zamponi et al, 2011).…”