Abstracts

Rationale: Vagal nerve stimulation was approved in the United States in 1997 as adjunctive therapy for intractable epilepsy in patients who are not suitable candidate for resective surgery. Thus we set out to assess the efficacy of VNS for intractable epilepsy in patient underwent implantation at university setting. Methods: This is a retrospective review of medical records of patients who underwent VNS implantation at University of Mississippi Medical Center between 2012 and 2015. The patient's population comprised of in hospital referral by epileptologists as well as patients referred by Neurologists in the community. The surgical implantation was performed by an epilepsy Neurosurgeon. Demographic data were collected and seizures outcome was assessed at one year following the implant. Patients who had VNS implanted for depression, patients with very limited history, or recent surgery with no follow-up, and surgery performed by ENT were excluded. Results: A total of 60 patients underwent VNS implant and 7 were excluded due to incomplete information following implantation. There were 32 males (60%) and 21 females, with mean age of 22 years and median of 26. 21 patients had daily seizures (56.8%), 4 patients had weekly seizures (10.8%), and 14 patients had monthly seizures (37.8%) and the rest of the patient's seizure dairy were incomplete. The average seizures frequency was 6.8/day. 52% had cryptogenic etiology, 13% static encephalopathy, 11% genetic and traumatic respectfully, 2% had infectious cause and 7% had structural abnormalities, however 2% of the etiology was not documented. 48% had GTC, 16% had partial seizures, and 30% had syndromic epilepsy with 9% had myoclonic and 11% atonic seizures. At one-year follow up; 31% had >90% reduction in seizures frequency including 2 patients were seizure free, and 28% had 60-90% reduction in seizures following VNS implant. Most of the patients were on multiple AEDs. At one year post-implant, 34% of the patients on 2-5 AEDs their medications were reduced, and 2% their AEDs were increased to 6, however none of the patients were off AEDs. Conclusions: This study demonstrates that the VNS is an effective therapy for refractory epilepsy patients. Out data is comparable to the earlier VNS outcome study and supports the VNS implantation in refractory patients who are not suitable for intracranial surgery. However in our study there are many patients that were not followed at the center, but Cyberonic could have centralized data down load which can be accessible even in patients that were followed by the community neurologist, parallel Neurpace paradigm. Funding: No funding source