Abstracts

RATIONALE: Because of a lack of 1. understanding of the mechanism of action of vagus nerve stimulation (VNS) and 2. responder identification studies, establishing practical guidelines for the use of VNS may lead to more adequate prescription and increased availability of VNS to larger patient populations. A first step in developing such guidelines is a review of current practice of VNS in Europe.
METHODS: Neurologists, neuropediatricians and neurosurgeons associated with 110 epilepsy centers in 17 European countries currently implanting devices were sent a structured questionnaire containing 28 questions with regard to diagnostic infrastructure, patient selection, specific therapeutic practice, patient follow-up, efficacy and side effects of VNS.
RESULTS: Between 9/2001 and 12/2001, 83/110 questionnaires from 17/17 countries were returned. 57 centers (71 %) were academical; 73 centers (87 %) had a monitoring unit with a mean number of 3 monitoring beds (range: 1-11) and a mean number of 117 monitoring sessions per year (range: 2-1000). 67 centers (81 %) reported having a dedicated multidisciplinary epilepsy team; 58 (70 %) commonly perform epilepsy surgery. Since 1989, a total number of 2639 devices were implanted; the mean number of implantations per center was 28 (range: 1-160). The main indications were refractory epilepsy not amenable by resective surgery and preferred alternative treatment for callosotomy (87% and 66% of centers, respectively). The main contra-indications were acute psychosis and cardiac conditions. 90% of centers use general anaesthesia. The mean duration of admission was 4 days (range: 1 - 60 days); the mean delay between implantation and activation of the device was 9 days (range: 0 - 125 days). The mean frequency of post-operative visits was 7 per year (range: 1-52). The reported efficacy of VNS matched results published in the literature in 63% of cases; results were felt to be worse in 30% and better in 8% of cases. Reported acute and chronic side effects matched the literature in 88% of centers; in 12% of centers other side effects were reported such as paralytic ileus, SUDEP, anorexia and sexual disturbances. Funding of the device was the main practical operational problem encountered by 40% of centers. 89% of centers estimated VNS to be a valuable addition the therapeutic armamentarium for refractory epilepsy
CONCLUSIONS: There seems to be a consensus among European epilepsy centers that VNS can be performed in patients with medically refractory epilepsy who are no surgical candidates. VNS is considered a preferred treatment option before callosotomy in 2/3 of European epilepsy centers. This wide scale review revealed no divergent results in terms of efficacy and side effects of VNS when compared to the presently available literature.
[Supported by: This work is supported by grant 01105399 from the Research Fund of Ghent University, by grants 1.5.236.99 and 6.0324.02 from the Fund for Scientific Research - Flanders and by the Clinical Epilepsy Grant of Ghent University Hospital 1998-2001]