Vagus nerve stimulation after lead revision.

Area of Science:

• Neurology
• Neurosurgery
• Biomedical Engineering

Background:

• Vagus nerve stimulation (VNS) is a proven therapy for intractable partial epilepsy.
• Hardware failures, particularly VNS lead issues, necessitate device replacement.
• Scar tissue around the vagus nerve complicates lead removal and revision.

Purpose of the Study:

• To characterize VNS lead failure and revision surgery outcomes.
• To evaluate VNS efficacy after placing a new lead on the same nerve segment.
• To assess the safety and effectiveness of VNS lead revision.

Main Methods:

• Retrospective review of 25 VNS lead revisions performed between 2001 and 2011.
• Analysis of patient records for reasons for revision, surgical duration, and outcomes.
• New lead placement on the previously stimulated vagus nerve segment in all cases.

Main Results:

• The most common cause for revision was lead failure (64%), leading to increased seizure frequency (72%).
• Revision surgery averaged 173 minutes, longer than initial implantation (94 minutes), but showed a trend toward shorter times with experience.
• 15 of 16 revised leads maintained VNS efficacy, comparable to the original lead's performance, with only one complication and no infections.

Conclusions:

• VNS lead revision surgery effectively restores seizure reduction comparable to initial implantation.
• Patients can achieve sustained VNS efficacy even after multiple lead revisions.
• Revision surgery has a learning curve and is longer than initial implantation, but remains safe with rare complications.