Abstracts

Long-term Impedence During Chronic Vagus Nerve Stimulation

Abstract number : 2.289
Submission category : 9. Surgery / 9B. Pediatrics
Year : 2022
Submission ID : 2204098
Source : www.aesnet.org
Presentation date : 12/4/2022 12:00:00 PM
Published date : Nov 22, 2022, 05:23 AM

Authors :
Cristine Cukiert, MD – Clinica Cukiert;

Rationale: VNS has been extensively used in the treatment of patients with refractory epilepsy and was shown to be effective in the treatment of children with generalized epilepsy who would otherwise not have been considered as good candidates for resective surgery. Impedance is an indirect measure of the stimulating electrode/nerve interface. We report on sequential impedance measurements during prolonged VNS in this pediatric population._x000D_
Methods: VNS has been extensively used in the treatment of patients with refractory epilepsy and was shown to be effective in the treatment of children with generalized epilepsy who would otherwise not have been considered as good candidates for resective surgery. Impedance is an indirect measure of the stimulating electrode/nerve interface. We report on sequential impedance measurements during prolonged VNS in this pediatric population._x000D_
Results: Impedance remained either stable (n=4) or decreased (n=16) over the 5 years of follow-up. Mean impedance was 2635-2576-2418-2340-2241 Ohms for years 1-5, respectively. This represented a 17% decrease in impedance over the first 5 years of therapy, or 76 Ohms yearly decrease in impedance during follow-up. Eighty percent of the patients were considered responders at last follow-up. There was no relationship between impedance values and outcome regarding seizures._x000D_
Conclusions: Significant scaring around the stimulating electrode-nerve unit has been noted during VNS reoperation procedures. On the other hand, the present data suggest that the electrode-nerve direct interface is preserved during chronic stimulation and might not affect treatment efficacy. A trend for a progressive decrease in impedance has also been noted in patients receiving DBS for treatment of both epilepsy and Parkinson’s disease. During reoperations, dissection of the peri-unit scar may be time consuming, but there is a free plane in the electrode-nerve interface itself and dissection for electrode removal or replacement could usually be carried out safely. _x000D_
Funding: None
Surgery