Authors :
Presenting Author: Kristin Nosova, MD – Banner University Medical Center - Phoenix
James Kelbert, BS – University of Arizona College of Medicine - Phoenix
Samuel Shapiro, BS – University of Arizona College of Medicine - Phoenix
Ganesh Murthy, MD – Banner University Medical Center - Phoenix
Khalid Alsherbini, MD – Banner University Medical Center - Phoenix
Robert Bina, MD – Banner University Medical Center - Phoenix
Rationale:
SRSE is status epilepticus that continues or recurs after 24 hours of continuous treatment with sedatives and anticonvulsants, including during tapering and discontinuation; mortality rates are estimated at 24%-40%. Traditional approaches often fail, highlighting the need for new treatment paradigms. The goal of the current report is to compare DBS vs RNS programming paradigms in treatment of SRSE.Methods:
We report five patients who underwent DBS or RNS placement for SRSE. Neuromodulation was considered after adequate trial of sedation using midazolam, pentobarbital, ketamine, and propofol and optimal selection and doses of anticonvulsants agents. Other therapies were used as appropriate. Selection of surgical modality and stimulation targets was based on clinical history, EEG, and imaging.Results:
RNS targets were tailored to epilepsy hypotheses. Systems were implanted 1, 3, and 6 weeks after admission. One patient underwent SSEG while two had target selection based on imaging findings and EEG. Patient 1: stimulation commenced post-implant day 3 and adjusted over 9 days; Patient 2: stimulation commenced on post-implant day 2 and adjusted over 27 days; Patient 3: stimulation commenced on post-implant day 1 and adjusted over 7 days. Programming including seizure detection and stimulation was tailored to each patient. One patient was switched from high frequency to low frequency stimulation due to continued SE. Charge densities were higher than typical: 7-10uC/cm2. Higher charge densities were tolerated in patients with centromedian nucleus likely due to IV anesthetics and comatose state at initial programming. Initial programming parameters varied according to the patterns recorded for each patient at implant location and response to lowest stimulation parameters. Decisions were based on daily review of S/EEG data and patient response.
Both DBS systems targeted the CMT. Entire system implant occurred 2.5 and 3 weeks after admission. Patient 4: stimulation commenced post-op day 3 at 2mA and increased to 3mA 2 days later; Patient 5: stimulation commenced at implant at 1.5mA. Initial programming parameters and changes were standard across patients with higher than standard initiation of stimulation that for DRE cases. After 48 hours, recording were reviewed and adjustments were made based on frequency band, EEG, and clinical responses. This was passive and did not affect ASM and sedative weaning in the ICU which was performed on EEG.
Four of five patients were under sedation at surgery; 3 were weaned within 4 days and 1 within 2 weeks. All patients were awake and following commands at discharge. The follow-up is 2+ years for two patients, more than one year for 2, and 6 months for the last. At last follow-up, two patients had meaningful seizure reduction and two continued to have daily seizures. One patient has been readmitted for SE. There was 0% mortality among patients.
Conclusions:
Conclusion: There is no significant difference in efficacy between RNS vs DBS for SRSE. The choice of modulation modality may be dictated by the ease of programming post-implantation but also tailored to the SRSE etiology and seizure localization.
Funding: Supported by Banner WISH Foundation Grant