Authors :
Presenting Author: Muhammad Ubaid Hafeez, MD – University of Texas Medical Branch Galveston
Komal Hafeez, MD – Clinical Fellow, Neurology, Baylor College of Medicine; Ramya 'Talanki Manjunatha, MD – Research Associate, Neurology, University of Texas Health Science Center Houston; Irfan Ali, MD – Assistant Professor, Neurology, Baylor College of Medicine; Daniel Curry, MD – Professor, Neurosurgery, Baylor College of Medicine; Jay Gavvala, MD – Associate Professor, Neurology, University of Texas Health Science Center Houston; Zulfi Haneef, MD – Associate Professor, Neurology, Baylor College of Medicine; Jaison Hampson, MD – Program Manager, Neurology, University of Texas Health Science Center Houston; Patrick Landazuri, MD – Associate Professor, Neurology, Kansas University Medical Center; Jacob Pellinen, MD – Assistant Professor, Neurology, University of Colorado School of Medicine; Manish Shah, MD – Associate Professor, Pediatric Neurosurgery, University of Texas Health Science Center Houston; Vishal Shah, MD – MD, Neurology, Kansas University Medical Center; Utku Uysal, MD – Associate Professor, Neurology, Kansas University Medical Center; Gretchen Von Allmen, MD – Professor, Pediatrics, University of Texas Health Science Center Houston; Nitin Tandon, MD – Professor, Neurosurgery, University of Texas Health Science Center Houston; Sandipan Pati, MD – Associate Professor, Neurology, University of Texas Health Science Center Houston
Rationale:
Responsive Neurostimulation (RNS) has emerged as a safe and effective therapeutic option for individuals with drug-resistant multifocal epilepsies. However, thalamic stimulation in drug-resistant generalized epilepsies, which are characterized by intralaminar thalamo-cortical network-driven generalized seizures, remains an area of growing interest. Previous small case series and studies have shown promising results using bilateral centromedian nuclei (CMN) as a potential target for neuromodulation in generalized onset seizures. This large retrospective multicenter study aims to explore the long-term clinical outcomes of patients with generalized epilepsies with bilateral CMN RNS.Methods:
This retrospective study was conducted across six level-IV epilepsy centers. Inclusion criteria included those over 12 years of age who received treatment with bilateral CMN RNS and met the following criteria: a) confirmation of generalized onset seizures (GOS) through video EEG, and b) presence of interictal spike-wave complexes and c) followed up > six months. Additionally, the cohort was further divided into two subgroups: Idiopathic Generalized Epilepsy (IGE) and Epileptic Encephalopathy (EE). The primary outcome was median percent change in patient-reported seizure frequency. The responder rate was defined as the percentage of patients achieving a ≥50% reduction in seizure frequency. The secondary outcome measures included changes in RNS-recorded long events and adverse events. The results are based on interim analysis with a final complete analysis planned in October 2023.Results:
Among the 19 patients who met the inclusion criteria, ten were diagnosed with IGE and nine with EE. The age range of the patients included in the study was between 16 and 38 years. The follow-up period post-implantation varied from six months to two years. In the IGE cohort, 9/10 patients achieved a >50% reduction in seizure burden at six months follow-up (Median 80%, Range: 66 – 100%), demonstrating a positive treatment response. Additionally, 2 patients in this cohort was reported sustained remission of tonic-clonic seizures at the last follow-up. Within the EE cohort, 4/9 patients achieved a >50% reduction in seizure burden, indicating a beneficial response to treatment. One patient required revision of electrode placement. Major surgical complications, such as bleeding and infection, were not observed. Two patients reported left-sided paresthesias. The occurrence of adverse events, including probable Sudden Unexpected Death in Epilepsy (SUDEP), was documented in one subject. The typical stimulation parameters utilized in the study included a high frequency of >100 Hz stimulation. The burst duration employed ranged from 100 ms to 5000 ms, providing insight into the range of stimulation durations used in the study.Conclusions:
This multicenter cohort study demonstrates the potential efficacy of bilateral CM RNS in patients with drug-resistant generalized epilepsies, particularly in the IGE subgroup. Significant reduction in seizure burden was observed, highlighting the positive impact of CMN RNS as a treatment option.
Funding: None