(Dibue-Adjei M, et al. 2017) A review of the literature on vagus nerve stimulation (VNS) therapy in patients with Dravet syndrome resulted in 13 studies (68 patients total). Of those patients, approximately 53% experienced a 50% reduction or more in seizures. Twenty-eight patients reported seizure data with enough detail to determine that the average seizure reduction was about 51%, suggesting controlled trials of VNS therapy in Dravet syndrome should be explored.

Dibué-Adjei M, Fischer I, Steiger HJ, Kamp MA. Efficacy of adjunctive vagus nerve stimulation in patients with Dravet syndrome: A meta-analysis of 68 patients. Seizure. 2017 Jun 17;50:147-152. doi: 10.1016/j.seizure.2017.06.007. [Epub ahead of print] Review. PubMed PMID: 28666193.