Neurostimulation as a Treatment Option for Epilepsy

Although neurostimulation is not a new treatment modality, it is an emerging treatment for various neurological diseases. Currently available pharmacological and surgical treatments leave about 30% of patients not seizure-free. Electrical stimulation of the 10th cranial nerve or vagus nerve stimulation (VNS) is an extracranial type of stimulation that is currently routinely available. Through an implanted device and electrode, electrical pulses are administered to the afferent fibres of the left vagus nerve in the neck. VNS is indicated in patients with refractory epilepsy who are unsuitable candidates for epilepsy surgery or who have had insufficient benefit from such a treatment. Intracerebral neurostimulation requires accessing the intracranial nervous system as stimulation electrodes are inserted into intracerebral targets for deep brain stimulation (DBS) or placed over the cortical convexity for cortical stimulation (CS). Recently, trials with DBS in different intracerebral structures such as the thalamus, the subthalamic nucleus and medial temporal lobe structures have been performed. CS ± DBS in a closed-loop system (responsive neurostimulator system [RNS]) is currently bein