Novel Use of Responsive Neurostimulation (RNS System) in the Treatment of Super Refractory Status Epilepticus

Abstract

There are very few randomized controlled trials studying treatment of super refractory status epilepticus (SE), despite estimated occurrence in about 15% of SE cases and its association with high morbidity and mortality rates. Small case series and case reports have described use of neurostimulation, including vagal nerve stimulation, transcranial magnetic stimulation, and deep brain stimulation, to treat super refractory SE when medical interventions have failed. To our knowledge, this is the first reported case of responsive neurostimulation being used to successfully treat a case of super refractory SE. A 37-year-old man with refractory focal epilepsy and a known focal cortical dysplasia involving motor cortex was implanted with an RNS System device after being in super refractory SE for 20 days. Responsive neurostimulation strip and depth electrodes were placed targeting the cortical dysplasia. Detection and stimulation parameters were adjusted over a 14-day period, as medications were gradually weaned. Seizures abated 15 days after implant, 24 hours after stimulation parameters were configured to mimic seizure offset pattern. Seizure remission was sustained, allowing the patient to be weaned off sedating medications and discharged to a rehabilitation facility. At 6 weeks of follow-up, the patient was near his neurologic baseline with no focal deficits.