Significant seizure frequency reduction in a patient with refractory bitemporal epilepsy following transition from high-frequency to low-frequency responsive neurostimulation

While many patients treated with Responsive Neurostimulation (RNS) experience a significant reduction in seizures, poor responders to traditional high frequency stimulation (HFS) may experience a meaningful reduction in seizure frequency when switched to low frequency stimulation (LFS). This case report presents a patient who developed post-traumatic pharmacoresistant bitemporal epilepsy and underwent unsuccessful treatments, including antiseizure polytherapy and implantation of a vagus nerve stimulator (VNS). Due to ongoing seizures, the patient underwent RNS System implantation with bilateral hippocampal depth electrodes. Prior to RNS implantation, the patient experienced a median frequency of 6.5 seizures per month. At traditional HFS settings applied for 30 months, the patient experienced a 31 % reduction from baseline. After switching to LFS for 8 months, the patient experienced an 85 % reduction. HFS delivered 6.02 min per day, compared to 113.77 min per day with LFS. This patient experienced a substantial and meaningful reduction in seizure frequency after switching to LFS, suggesting that LFS may be an effective alternative for RNS patients who do not have a satisfactory seizure reduction to traditional HFS. Furthermore, this case report highlights the importance of collaboration between academic medical centers with public safety net hospitals in delivering advanced epilepsy care to people in underserved communities.