An exploration of deep brain stimulation parameters on the burden of epileptic discharges in Lennox-Gastaut syndrome.
Abstract number :
1.313
Submission category :
4. Clinical Epilepsy / 4C. Clinical Treatments
Year :
2025
Submission ID :
531
Source :
www.aesnet.org
Presentation date :
12/6/2025 12:00:00 AM
Published date :
Authors :
Presenting Author: Michael Ginevra, MD – University of Melbourne
John Archer, MD, PhD – University of Melbourne
Linda Dalic, MD, PhD – University of Melbourne
Rationale: Lennox-Gastaut syndrome (LGS) is a severe epileptic encephalopathy with drug-resistant seizures. Deep brain stimulation (DBS) of the centromedian nucleus (CM-DBS) shows promise, but optimizing stimulation parameters for improved outcomes remains a challenge. Generalized paroxysmal fast activity (GPFA) burden has been identified as a biomarker for CM-DBS treatment response in LGS. This study aims to explore whether different CM-DBS parameters are associated with varying GPFA burden, thereby providing potential guidance for more rapid optimization of stimulator settings.
Methods: Ten patients with LGS who had previously undergone CM-DBS were recruited for a 5-day inpatient stay with continuous video-EEG monitoring. DBS settings were adjusted daily to explore four conditions: (1) Baseline (standard settings), (2) "Pf" (deeper electrode contact), (3) Rapid Cycling (10 sec on/50 sec off), and (4) 2Hz Constant (continuous 2Hz stimulation). GPFA burden was quantified over a 2-hour sleep window each night using three measures: total number of GPFA events, total duration of GPFA, and percentage of the record occupied by GPFA. Statistical analysis involved single-factor ANOVA to assess group-level differences.
Results: A total of 12,794 GPFA discharges were identified across 80 hours of EEG recordings. While all three measures of GPFA burden were highly correlated (>0.94), single-factor ANOVA revealed no significant group-level difference in GPFA burden among the four stimulation settings (p=0.48,F=0.85). The mean total duration of GPFA was 424.1 seconds at baseline, 301.5 seconds for "Pf", 318.3 seconds for rapid cycling, and 353.9 seconds for 2Hz constant stimulation. Notably, significant inter-patient variability in response to the different settings was observed, with some individuals showing substantial reductions or increases in GPFA burden for specific parameters (e.g., 50% of patients experienced a >20 reduction in GPFA burden with rapid cycling, while 40% saw an increase).
Conclusions: This exploratory study found no significant group-level effect of different CM-DBS stimulation parameters on GPFA burden in LGS patients. However, the considerable individual variability in response highlights the potential for personalized optimization of DBS settings. Further research is needed to determine if this variability reflects true inter-individual differences in optimal stimulation parameters or day-to-day fluctuations in GPFA burden, and to correlate these changes with long-term seizure outcomes.
Funding: National Health and Medical Research Council (NHMRC) Early Career's Researcher grant - awarded to Dr Linda Dalic - Australia
Clinical Epilepsy