Abstracts

Rationale: Despite the undebatable benefits of Vagal Nerve Stimulation (VNS) for thousands of patients with intractable epilepsies, there is still no clearcut determination of which patients could benefit most from this therapy.  Methods: Thirteen focal epilepsy patients submitted to VNS implantation were followed prospectively. At each visit for increase in stimulation current, seizure frequency was recorded based on seizure diaries. A seizure frequency X stimulation current graph was obtained for each patient. Power trendlines were generated on Powerpoint. Modifications in drug treatment and other variables possibly interfering on seizure frequency were not accounted for.  Results: Eight patients had frontal lobe seizures and five had them originating in the temporal lobes, as demonstrated by scalp video-EEG monitoring. All patients showed descending trendlines, indicating overall reduction in seizure frequency as stimulation current was increased. All except one patient from the frontal lobe group showed steeper trendlines, indicating an earlier response to VNS therapy, as compared to the temporal lobe group. From this group, only one patient showed a fast reduction in seizure frequency and most presented a smoother decrease.  Conclusions: Patients with frontal lobe epilepsy seem to show an earlier response to VNS, when compared to temporal lobe epilepsy patients. Larger numbers are needed to validate this finding.  Funding: No funding