Effect of Vagal Nerve Stimulation on Gastric Motor Functions

Inclusion Criteria Subject must be at least 18 years old. Subject must provide written informed consent and Health Insurance Portability and Accountability Act (HIPAA) authorization Disabling seizures (Disabling seizures are those with significant negative impact on the patient's life) Drug Resistant Epilepsy, with continuing seizures despite adequate trials of at least 2 appropriate anti-seizure drugs (ASDS) with therapeutic serum concentrations (as per the International League Against Epilepsy (ILAE) Commission on Therapeutic Strategies) (44). Not a good candidate for resective surgery as determined by our institution's multidisciplinary epilepsy surgery committee Apart from epilepsy, subject should be medically and neurologically stable. Subject is able to complete regular office visits and telephone appointments including the 2 imaging sessions in accordance with the study protocol requirements. Subject is a male or non-pregnant female adequately protected from conception, or willing to use an acceptable method of birth control over the entire study duration if of childbearing potential. Subject has been informed of his or her eligibility for resective surgery as a potential alternative to the study if such surgery is a reasonable option. 4.2 Exclusion Criteria Subject currently uses or during the study is expected to use short-wave diathermy, microwave, diathermy, or therapeutic ultrasound diathermy. Subject has a substance abuse history (alcohol, prescription, or illicit medications) within the preceding two years. Subject participated in another drug or device trial within the preceding 30 days (other than the REVEAL main CSP). Subject has been hospitalized for a psychiatric condition within the preceding two years or has had a history of psychosis within the preceding two years (excluding post-ictal psychosis). Subject has experienced unprovoked status epilepticus in the preceding year. Subject is on anticoagulants and is unable to discontinue them peri-surgically, as required by the neurosurgeon or Investigator. Subject has significant platelet dysfunction from medical conditions or medications (including, particularly, aspirin or sodium valproate). If platelet dysfunction is suspected, subject can be enrolled only if a hematologist, the Investigator, and the neurosurgeon judge it to be advisable. Subject with vocal cord paralysis Any other factor that may impact participant safety or compliance as per PI. Subject cannot speak and read English. Prohibited Therapy During Study Period: We will exclude patients on immunosuppressants, beta blockers, anticholinergics, and clonidine. Consultation with primary providers and amending some of these therapies may be allowed only if clinically indicated. In that case, participants will have to be stable on their new medication for at least one month prior to implant. A body weight of over 350 pounds or 159 kilograms due to equipment limitations used in the measurements of gastric accommodation and emptying. An inability to eat eggs whether due to an allergy, intolerance, or strong dislike. The gastric emptying test meal contains eggs that are labeled with radioisotope. Other food substitutions for the toast, butter and milk may be made only if prior approval is given by Dr. Camilleri.