Intracranial Neuromodulation for Treatment of Super Refractory Status Epilepticus: Case Series and Review of Literature

Introduction: Super refractory status epilepticus (SRSE) causes high morbidity and mortality of up to 30-50%. There are no established treatment guidelines for SRSE. Here, the authors present a series of SRSE patients treated with intracranial neurostimulation and review the published literature.

Methods: Retrospective chart review of patients treated with intracranial neurostimulation for SRSE was performed to extract clinical and demographic variables. PubMed was used to perform a literature review on use of intracranial neurostimulation to treat SRSE.

Results: Three adult SRSE patients—two with focal and one with generalized status epilepticus—were treated with intracranial neurostimulation. The two focal cases had seizure foci in the primary motor cortex and received responsive neurostimulation (RNS) within two weeks of SRSE onset, leading to resolution of SRSE and significant long-term seizure reduction. The patient with generalized status epilepticus received deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) around six weeks after SRSE onset. Anesthetic medications were successfully weaned, and the patient was discharged but unfortunately died five weeks postoperatively due to cardiac arrest.

Intracranial neurostimulation shows potential as a treatment for SE. Our literature review including 16 patients (1 NORSE, 3 FIRES, 12 SRSE) treated with RNS (n = 4) and DBS (n = 12) showed reduction or complete resolution of seizures post-stimulation with improved long-term outcome in fourteen patients. Two DBS patients had complications: one had implants removed due to infection despite seizure reduction, and one had a transient increase in generalized seizures despite reduction in focal seizures.

Conclusion : Published reports of intracranial neurostimulation demonstrate high efficacy in treating SRSE, with reporting bias potentially playing a role. While most patients experienced termination of SRSE and long-term seizure reduction, others persisted in SRSE. Further studies are needed to determine optimal timing of treatment as well as target nuclei and modality of neurostimulation.