Intracranial Post-ictal Attenuation (IPA) Is Associated with Ongoing Generalized Tonic-clonic Seizures (GTCs) in Patients Implanted with Responsive Neurostimulator (RNS)
Abstract number :
1.118
Submission category :
2. Translational Research / 2C. Biomarkers
Year :
2022
Submission ID :
2204195
Source :
www.aesnet.org
Presentation date :
12/3/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:23 AM
Authors :
Franklyn Rocha-Cabrero, MD – Imperium RevDoc Neuroanalysis; Anna Zolyan, MD – Resident Physician, Neurology, University of California, Irvine; Rabia Yasin, MBBS – Epileptologist, University of California, Davis; Kenneth Ndyabawe, PhD – Field Clinical Engineer, NeuroPace, Inc.; Emily Mirro, B.S., M.B.A – Senior Director of Clinical Education and Collaboration, NeuroPace, Inc.; Merit Vick, B.A. S.c. – Field Clinical Manager, NeuroPace, Inc; Jack Lin, MD, Clinical Professor – Director & Clinical Professor, UC Davis Comprehensive Epilepsy Program, Neurology, University of California, Davis; Jeffrey Kennedy, MD – Clinical Associate Professor, UC Davis Comprehensive Epilepsy Program, Neurology, University of California, Davis; Indranil Sen-Gupta, MD – Clinical Associate Professor and Director of Clinical Neurophysiology and Epilepsy Fellowship, UCI Comprehensive Epilepsy Center, Neurology, University of California, Irvine
Rationale: Occurrence of ≥3 GTCs/year is associated with a 15-fold increased risk of SUDEP. Scalp post-ictal generalized EEG suppression (PGES) occurs in 40-66% of adults with GTCs and may be a promising biomarker of SUDEP risk in refractory epilepsy. Analogously, IPA has also been reported as a hallmark of GTCs in patients undergoing invasive surgical epilepsy evaluations. We therefore queried whether IPA observed in patients implanted with RNS correlates with clinical history of ongoing GTCs, which in turn may relate to refractory epilepsy and SUDEP risk.
Methods: Retrospective analysis of patients implanted with RNS at the UC Irvine Medical Center was performed (N=30) spanning from implantation through February 2022. Analysis included manual review of all available RNS electrocorticography (ECoG) tracings in NeuroPace PDMS by an investigator (FRC), and chart review for documented history of GTCs. IPA was considered present for a patient if attenuation of < 50 uV for at least 5 seconds was noted in any channel following an RNS ECoG seizure (Figure 1). Odds ratios for IPA on RNS ECoG tracings and GTCs were computed in the following analysis settings: (1) any documented history of GTC (prior to and/or after RNS implantation), and (2) documented GTC following RNS implantation.
Results: The first analysis did not demonstrate significantly elevated frank odds of IPA on RNS ECoG in the setting of any history of GTC either prior to and/or after RNS implantation (OR 1.36, 95% CI [0.16-11.23], p = 0.77). Moreover, there was no significant difference between the proportion of patients with IPA who had any history of GTC versus the proportion of patients without IPA who had any history of GTC (15/17 [88.2%] vs. 11/13 [84.6%], respectively; p = 0.77). However, the second analysis revealed significantly elevated odds of documented GTC specifically following RNS implantation and the finding of IPA on RNS ECoG (OR 13.5, 95% CI [1.42-128.26], p < 0.05; Table 1 A-B).
Translational Research