Epicranial focal cortex stimulation for minimally invasive neuromodulation of the epileptogenic region: A review.

Epicranial focal cortex stimulation (FCS) is a new type of neurostimulation for pharmacoresistant focal epilepsy, which has recently been CE-certified for treatment of European patients. Stimulation is performed via an epicranially placed five-contact electrode array, which applies high frequency stimulation and DC-like cathodal stimulation to the individual epileptogenic brain region. Stimulation at appropriate intensities is not perceived by patients, and first evidence from two prospective unblinded clinical trials suggests excellent tolerability of both, subgaleal implantation and transcranial stimulation. In epilepsies arising from the dorsolateral brain convexity, FCS resulted in a median seizure reduction of >50 % after 6 months which further increased to >60 % after 2 years. This compares favorably to more invasive neurostimulation approaches.