Responsive Neurostimulation for Treatment of SCN1A-Associated Developmental and Epileptic Encephalopathies
Abstract number :
3.409
Submission category :
9. Surgery / 9B. Pediatrics
Year :
2025
Submission ID :
603
Source :
www.aesnet.org
Presentation date :
12/8/2025 12:00:00 AM
Published date :
Authors :
Presenting Author: Audie Espinoza, MD – University of Utah School of Medicine
Erin Willis, MD – Univesity of Arkansas for Medical Sciences
Olivia Kim-McManus, MD – Rady Children's Institute for Genomic Medicine
Deborah Holder, MD – Cedars-Sinai Guerin Children's Hospital
Reilly Philliben, DO – University of Utah School of Medicine
Rationale: SCN1A-associated epilepsies, including Dravet syndrome, are severe developmental and epileptic encephalopathies marked by early-onset, drug-resistant seizures. While responsive neurostimulation (RNS) is approved for focal epilepsy, its role in generalized and multifocal epilepsies remains underexplored. Growing evidence supports thalamic stimulation as a promising strategy for modulating seizure networks, though data on RNS use in SCN1A-associated epilepsy remain sparse. We present a multi-institutional case series evaluating the safety, outcomes, and stimulation strategies of RNS in this population.
Methods: We retrospectively reviewed six patients with pathogenic SCN1A variants treated with RNS across multiple centers (Table 1). Data included epilepsy phenotype, seizure semiology and frequency, age at implantation, lead placement, prior therapies, stimulation parameters, and clinical outcomes. RNS responders were defined as patients with ≥50% seizure reduction at last follow-up.
Results: All six patients had early-onset, drug-resistant epilepsy with mixed seizure types (generalized tonic-clonic, myoclonic, atypical absence, hemiclonic, and focal). Five met criteria for Dravet syndrome; one had generalized epilepsy with febrile seizures plus (GEFS+). Patients were treated with two to six antiseizure medications; three had vagus nerve stimulation (VNS), and three had trialed the ketogenic or modified Atkins diet. RNS was implanted at a median age of 13 years (range 6–21). Five patients had bilateral thalamic leads—four to the centromedian nucleus (CMN), one to the anterior nucleus (ANT); one had bilateral frontal strip leads. Stimulation parameters varied across patients (Table 2). Follow-up ranged from 3 to 54 months. At last follow-up, 4/6 patients (66%) were responders. One achieved 9 months of seizure freedom at time of report; another had complete resolution of myoclonic and atonic seizures; and a third had selective resolution of generalized tonic-clonic seizures with no further episodes of status epilepticus. Among responders, additional quality-of-life (QOL) improvements included reduced reliance on medical equipment and rescue medication, fewer hospitalizations, improved school performance, and shorter postictal recovery. Both non-responders reported cognitive gains despite < 50% seizure reduction. No ongoing stimulation-related complications were observed.
Conclusions: This multi-institutional case series adds to the growing evidence supporting RNS in drug-resistant generalized and multifocal epilepsies, including Dravet syndrome. Most patients experienced meaningful seizure reduction and QOL improvements, suggesting RNS may be a viable option in this population. Bilateral thalamic stimulation was the most common approach, reflecting increased use of network-targeted neuromodulation in generalized epilepsy. Future studies with larger cohorts are needed to define optimal lead placement, stimulation settings, and predictors of response. RNS was well tolerated, supporting its safety in this medically refractory population.
Funding: NA
Surgery