Revision and removal of vagus nerve stimulation systems: twenty-five years' experience

Lydia Kaoutzani; Liam V Goldman; Keaton Piper; Manish Kumar; Fernando L Vale

doi:10.1007/s00701-023-05875-1

Revision and removal of vagus nerve stimulation systems: twenty-five years' experience

Acta Neurochir (Wien). 2023 Dec;165(12):3913-3920. doi: 10.1007/s00701-023-05875-1. Epub 2023 Nov 14.

Authors

Lydia Kaoutzani¹, Liam V Goldman¹, Keaton Piper², Manish Kumar^{1

3}, Fernando L Vale⁴

Affiliations

¹ Department of Neurosurgery, Medical College of Georgia, Augusta University (MCG-AU), Augusta, GA, USA.
² Department of Neurosurgery, University of South Florida (USF), Tampa, USA.
³ Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA.
⁴ Department of Neurosurgery, Medical College of Georgia, Augusta University (MCG-AU), Augusta, GA, USA. FVALEDIAZ@augusta.edu.

PMID: 37957310
DOI: 10.1007/s00701-023-05875-1

Abstract

Background: Epilepsy, a disease characterized by recurrent seizures, is a common chronic neurologic condition. Antiepileptic drugs (AED) are the mainstay of treatment for epilepsy. Vagus nerve stimulation (VNS) surgery is an adjuvant therapy for the treatment of drug refractory epilepsy (DRE). VNS revision and implant removal surgeries remain common.

Methods: Using a single neurosurgeon data registry for epilepsy surgery, we retrospectively analyzed a total of 824 VNS surgeries. Patients were referred to two Level IV Comprehensive Epilepsy centers (from 08/1997 to 08/2022) for evaluation. Patients were divided into four groups: new device placement, revision surgery, removal surgery, and battery replacement for end-of-life of the generator. The primary endpoint was to analyze the reasons that led patients to undergo revision and removal surgeries. The time period from the index surgery to the removal surgery was also calculated.

Results: The median age of patients undergoing any type of surgery was 34 years. The primary reason for revision surgeries was device malfunction, followed by patients' cosmetic dissatisfaction. There was no statistical sex-difference in revision surgeries. The median age and body mass index (BMI) of patients who underwent revision surgery were 38 years and 26, respectively. On the other hand, the primary reason for removal was lack of efficacy, followed again by cosmetic dissatisfaction. The survival analysis showed that 43% of VNS device remained in place for 5 years and 50% of the VNS devices were kept for 1533 days or 4.2 years.

Conclusions: VNS therapy is safe and well-tolerated. VNS revision and removal surgeries occur in less than 5% of cases. More importantly, attention to detail and good surgical technique at the time of the index surgery can increase patient satisfaction, minimize the need for further surgeries, and improve acceptance of the VNS technology.

Keywords: Drug-resistant epilepsy; Removal surgery; Revision surgery; Vagus nerve stimulation.

MeSH terms

Adult
Drug Resistant Epilepsy* / surgery
Epilepsy* / therapy
Humans
Reoperation
Retrospective Studies
Treatment Outcome
Vagus Nerve
Vagus Nerve Stimulation*