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Vagus nerve stimulation therapy for the treatment of epilepsy

Author
Steven C Schachter, MD
Section Editor
Timothy A Pedley, MD
Deputy Editor
April F Eichler, MD, MPH

INTRODUCTION

Antiseizure drugs are the most often used treatment for patients with epilepsy. However, in approximately one-third of people with epilepsy, medications do not completely control seizures [1]. The seizures that occur in these patients are referred to as refractory or drug-resistant.

In patients with refractory epilepsy, various combinations of antiseizure medications may be tried. Although combination therapy may help to reduce the total number of seizures, polypharmacy often leads to an increased number of side effects. Nonpharmacologic options are therefore an important component of the overall therapeutic approach to refractory epilepsy. One such option is vagus nerve stimulation (VNS) therapy; others include epilepsy surgery, ketogenic diet, and responsive neurostimulation.

This topic reviews the relevant anatomy, possible mechanisms of action, and clinical results of VNS in patients with epilepsy. Other aspects of epilepsy treatment in both children and adults are discussed separately. (See "Overview of the management of epilepsy in adults" and "Evaluation and management of drug-resistant epilepsy" and "Surgical treatment of epilepsy in adults" and "Seizures and epilepsy in children: Initial treatment and monitoring" and "Seizures and epilepsy in children: Refractory seizures and prognosis" and "The ketogenic diet and other dietary therapies for the treatment of epilepsy".)

MECHANISM OF EFFECT

The precise mechanisms by which vagus nerve stimulation (VNS) therapy achieves seizure reduction are not well established. A variety of nonexclusive mechanisms have been proposed and are partially supported by animal and human studies, including:

Afferent vagal projections through the pontine parabrachial nucleus and thalamus to seizure generating regions in the basal forebrain and insular cortex [2,3]

                                    

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Literature review current through: Nov 2016. | This topic last updated: Thu Oct 13 00:00:00 GMT+00:00 2016.
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References
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