A systematic review of magnetic resonance imaging in patients with an implanted vagus nerve stimulation system.

PURPOSE: Vagus nerve stimulation (VNS) is an effective adjunctive treatment for drug-resistant epilepsy (DRE) and difficult-to-treat depression (DTD). More than 125.000 patients have been implanted with VNS Therapy® System (LivaNova PLC) since initial approval. Patients with DRE often require magnetic resonance imaging (MRI) of the brain during the course of their disease. VNS Therapy System devices are labeled to allow MRI under certain conditions; however, there are no published comprehensive articles about the real-world experience using MRI in patients with implanted VNS devices. METHODS: A systematic review in accordance with PRISMA statement was performed using PubMed database. Full-length articles reporting MRI (1.5 T or 3 T scanner) of patients with implanted VNS for DRE or DTD and published since 2000 were included. The primary endpoint was a positive outcome that was defined as a technically uneventful MRI scan performed in accordance with the VNS Therapy System manufacturer guidelines and completed according to the researchers' planned scanning protocol without harm to the patient. RESULTS: Twenty-six articles were eligible with 25 articles referring to the VNS Therapy System, and 216 patients were included in the analysis. No serious adverse events or serious device-related adverse events were reported. MRI scan was prematurely terminated in one patient due to a panic attack. CONCLUSION: This systematic review indicates that cranial MRI of patients with an implanted VNS Therapy System can be completed satisfactorily and is tolerable and safe using 1.5 T and 3 T MRI scanners when performed in adherence to the VNS manufacturer's guidelines.

Training and teaching of vagus nerve stimulation surgery: Worldwide survey and future perspectives.

OBJECTIVE: Vagus nerve stimulation (VNS) therapy has been used for more than two decades to treat drug resistant epilepsy and depression and most recently received FDA approval for stroke rehabilitation. Expanding indications will renew the interest in the technique and increase the number of surgeons to be trained. The aim of this study was to survey surgeons with substantial expertise on optimal teaching and training approaches. METHODS: Anonymous forms comprising 16 questions were sent by e-mail to surgeons with substantial expertise. Statistical analyses were used to compare the answers of the most experienced surgeons (>5 years) with the less experienced ones (<5 years). RESULTS: Fully-completed forms were collected from 57 experts from 20 countries. The placement of the helical coils was deemed to be the most difficult step by 36 (63.2%) experts, and the use of optical magnification during this step was deemed necessary by 39 (68.4%) experts. Vocal cord palsy should be largely avoidable with proper surgical technique according to 44 (77.2%) experts. The teaching tool considered the most useful was mentoring (38, 66.7%). The future of VNS surgery teaching was deemed to be in anatomical workshops (29, 50.9%) and surgical simulation (26, 45.6%). Overall, answers did not vary significantly according to experience. CONCLUSIONS: VNS surgery should be mastered by actively participating in dedicated practical training courses and by individual mentoring during actual surgery, which is still the best way to learn. This study highlights the need for a formal training course and possible specific accreditation.