Role of Morphology in Interictal Spikes to Elucidate Seizure Generation
Abstract number :
2.436
Submission category :
3. Neurophysiology / 3G. Computational Analysis & Modeling of EEG
Year :
2023
Submission ID :
1322
Source :
www.aesnet.org
Presentation date :
12/3/2023 12:00:00 AM
Published date :
Authors :
Presenting Author: Carlos Aguila, BS – University of Pennsylvania
Erin Conrad, MD – University of Pennsylvania; Brian Litt, MD – University of Pennsylvania; Devin ma, BS – University of Pennsylvania; Akash Pattnaik, BS – University of Pennsylvania; Alfredo Lucas, MS – University of Pennsylvania; Joshua LaRocque, MD, PhD – University of Pennsylvania
Rationale: Patients with drug-resistant epilepsy undergo intracranial EEG (iEEG) during presurgical evaluation. Accurate localization of the seizure onset zone (SOZ) during this evaluation is crucial for successful intervention like surgical resection and radiofrequency (RF) ablation. Interictal spike data informs clinical decision-making. Currently, clinical teams qualitatively review spike patterns on iEEG. To enhance our understanding of the brain tissue responsible for generating seizures, this study introduces a rigorous quantitative methodology for the analysis of spike morphology, with a focus on interpreting regional variations in spike characteristics.
Methods: A total of 138 patients diagnosed with drug-resistant epilepsy underwent iEEG to localize epileptic tissue. All recordings were re-referenced to a common average reference montage and electrodes were mapped to specific anatomical brain regions through the utilization of an automatic registration pipeline. An automatic, previously validated spike detection algorithm was used to find interictal spikes. For each spike, the following morphological features were extracted: rising and falling amplitude, slow wave height and width, rising and falling slope, and line length. We compared features between anatomical brain regions and between SOZ and non-SOZ electrodes within brain regions.
Results: There was no difference in spike morphology between SOZ and non-SOZ-containing brain regions (p > 0.05). Mixed effect linear models that controlled for patient effect demonstrated that the rising and falling amplitude and line length of spikes were significantly greater in the hippocampus, amygdala, parahippocampal gyrus, and entorhinal regions. Within brain regions, several features differed between SOZ and non-SOZ electrodes (p < 0.001 for rising amplitude, falling amplitude, slow wave height, line length).
Neurophysiology