Overview

Vagal nerve stimulation is a neurosurgical procedure consisting of implantation of an impulse generator battery with leads placed into the vagus nerve in the neck. This procedure was FDA approved for epilepsy in the 1990s and is commonly performed as an outpatient surgery. The mechanism of efficacy is not well understood; however it is increasingly recognized that electrical stimulation of the vagus nerve may impact other organ systems in the body including the immune, gastrointestinal and autonomic systems. The primary objective of this study is to characterize the pre- and post-operative bowel habits and gut microbiome of patients implanted with vagal nerve stimulator (VNS) for epilepsy. Secondary objectives of this study include: (1) to characterize the pre- and post-operative autonomic profile, (2) characterize the pre- and post-operative immune profile, and (3) to elucidate whether gut microbiota changes are related to VNS efficacy for epilepsy.

Eligibility

Inclusion Criteria:

• Undergoing VNS implantation for the first time as a treatment for epilepsy
• Documented follow up with a Louisville-based neurologist in the past 1 year or documented ability to follow to travel to Louisville for outpatient medical care

Exclusion Criteria:

• Previous treatment with VNS
• Current pregnancy (contraindication to surgery)
• History of chemotherapy
• Treatment with cholinergic or anticholinergic medication in the past month or during the study period
• Pre-existing cardiac arrythmia or presence of cardiac pacemaker/defibrillator
• Treatment with immunomodulator in the past month or during the study period
• Treatment with steroids in the past month or during the study period
• History of cancer