Revision of vagal nerve stimulator electrodes: technical approach.
BACKGROUND
As the number of implanted vagal nerve stimulators grows, the need for removal or revision of the devices will become more frequent. Our purpose was to demonstrate the feasibility of complete removal of the vagal nerve stimulator electrode using microsurgical technique.


METHODS
. Operative databases at the University of Utah (1995 through 2002), Westchester Medical Center (1995 through 2001), and University of Arizona Health Sciences Center (1995 through 1999) were retrospectively reviewed. Patients who had undergone removal or revision of a previously placed vagal nerve stimulator electrode were identified. Patients who had a vagal nerve stimulator device removed but had the lead trimmed and incompletely removed were excluded.


RESULTS
Seven patients underwent complete removal of the lead. Microsurgical dissection allowed removal of the helical electrode from the vagus nerve without apparent physiological consequences. Four patients had a new electrode placed just proximal to the original lead site. The operative procedure required an additional 30 minutes to complete compared with initial device placement. The four patients who underwent replacement of the electrode demonstrated normal device function and lead resistance at the time of postoperative follow-up. Each experienced a return to prior stimulation response and seizure control.


CONCLUSIONS
This series suggests that the electrode can be removed from the vagus nerve and repositioned without significant consequence in most cases.
MacDonald
J
J
Department of Neurosurgery, University of Utah Health Sciences Center, Salt Lake City, Utah 84132, USA. vasospaz@aol.com
Couldwell
W T
WT
D000328:Adult; D020878:Device Removal; D004210:Dissection; D004599:Electric Stimulation Therapy / Q000295:instrumentation*; D004567:Electrodes, Implanted; D004827:Epilepsy / Q000628:therapy*; D004868:Equipment Failure; D005260:Female; D006801:Humans; D008297:Male; D008866:Microsurgery; D012086:Reoperation; D012189:Retrospective Studies; D014630:Vagus Nerve / Q000503:physiopathology* / Q000601:surgery