Centromedian nucleus targeting in the pediatric population treated with thalamic responsive neurostimulation for drug‐resistant epilepsy

The management of drug-resistant epilepsy (DRE) in the pediatric population using neurostimulation of the centromedian (CM) nucleus of the thalamus (CMN) has been reported to be effective and safe. We present a case series of pediatric patients treated with responsive neurostimulation (RNS) and report on contact localization in relation to preliminary outcomes, specifically seizure reduction rates. Thirteen pediatric patients treated with RNS underwent direct targeting of the CMN based on Magnetization-Prepared 2 Rapid Gradient-Echo (MP2RAGE) scans, using ClearPoint neuronavigation. The implanted electrodes were co-registered to a probabilistic anatomical model of the thalamic nuclei (Freesurfer) for secondary confirmation of contact localization. Ten out of the 12 patients with extra-temporal multifocal or generalized DRE (83.3%) had over 50% reduction in seizures, benefiting from an 80.4% seizure reduction rate. The average follow-up interval was 25.2 months, with no patients experiencing stimulation-related side effects. The analysis of post-operative images revealed that out of the 24 CM-processed electrodes, 23 (95.8%) had at least two contacts in the nucleus, based on patient-specific segmentation of the thalamus. The preliminary outcomes suggest a robust response to central neurostimulation and no stimulation-related side effects in pediatric patients suffering from multifocal or generalized DRE when implementing high-accuracy direct targeting. PLAIN LANGUAGE SUMMARY: We are reporting our experience in the management of the most challenging types of pediatric epilepsy, involving seizures originating from multiple and/or poorly defined brain areas. We surgically implanted a responsive neurostimulation device (RNS) in central areas of the brain that function as connection hubs between different brain regions. These devices are designed to detect early signs of abnormal brain activity, and respond with electrical pulses to prevent progression to clinical seizures. Using our approach, we reduced the seizure rates by an average of 80% in 83% of the pediatric patients who received this treatment.