Vagus Nerve Stimulation for Treatment of Epilepsy: Rush Epilepsy Center's Experience
Abstract number :
2.026
Submission category :
Year :
2000
Submission ID :
1253
Source :
www.aesnet.org
Presentation date :
12/2/2000 12:00:00 AM
Published date :
Dec 1, 2000, 06:00 AM
Authors :
Ruzica K Ristanovic, Bess Chang, Sue Leurgans, Donna Bergen, Andres M Kanner, Michael Smith, Richard W Byrne, Walter Whisler, Elena Hung, Linda Smith, Marlis Frey, Rush-Presbyterian Saint Luke's Medical Center, Chicago, IL.
RATIONALE: The objective of this analysis was to determine the long-term efficacy of the vagus nerve stimulation (VNS) as adjunctive therapy in patients treated at Rush Epilepsy Center. METHODS: Since 1990 till the end of 1999, 84 patients were implanted. 75/84 patients were evaluable. Follow-up time averaged 22 months(range 3 months - 9 years). Seven patients had 5 or more years follow-up information. The mean age at implant was 26.8(range 3.6 - 58.1). Eight patients (11%) were under 12 years of age, and seven (10%) were over 45. Median seizure frequency at baseline was 1.22 seizures/day. 66% of patients had localization-related symptomatic epilepsy, mainly due to mesial temporal sclerosis, encephalitis and trauma. Average number of medications was 2.3 (SD 1.0). A declining number (DN) analysis and the last-visit-carried-forward (LVCF) are reported (Wilcoxon signed-rank test). RESULTS: Median percent seizure reduction of secondarily generalized seizures parallels changes in partial seizures (Table #1) (Wilcoxon p? .005 for LVCF). Proportion of patients with ?50% seizure reduction also steadily increases over time from 30% at 3 months to 48% at 24 months. CONCLUSIONS: Overall long-term efficacy data in this population of patients is consistent with published reports, suggesting sustained and increasing time-dependent cumulative benefit in seizure control.