Localization of the Epileptogenic Zone Using Spatial and Temporal Volatility of Phase-amplitude Coupling
Abstract number :
1.195
Submission category :
3. Neurophysiology / 3G. Computational Analysis & Modeling of EEG
Year :
2022
Submission ID :
2203933
Source :
www.aesnet.org
Presentation date :
12/3/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:22 AM
Authors :
Keiki Inoue, – Department of Pediatrics, Children's Hospital of Michigan, Wayne State University; Naoto Kuroda, MD – Department of Pediatrics, Children's Hospital of Michigan, Wayne State University,Department of Epileptology, Tohoku University Graduate School of Medicine; Aimee Luat, MD – Department of Pediatrics, Children's Hospital of Michigan, Wayne State University,Department of Neurology, Children's Hospital of Michigan, Wayne State University; Neena Marupudi, MD,MS – Department of Neurosurgery, Children's Hospital of Michigan, Wayne State University; Sandeep Sood, MD – Department of Neurosurgery, Children's Hospital of Michigan, Wayne State University; Eishi Asano, MD,PhD – Department of Pediatrics, Children's Hospital of Michigan, Wayne State University,Department of Neurology, Children's Hospital of Michigan, Wayne State University
Rationale: Rationale: Modulation index (MI), quantifying the phase-amplitude coupling between interictal high-frequency oscillation (HFO) amplitude at >150 Hz and delta waves at 3-4 Hz, is a promising biomarker to localize the epileptogenic zone. The present study explored the diagnostic utility of spatial and temporal volatility of MI (MIsv and MItv) in epilepsy presurgical evaluation.
Methods: We studied 135 patients who underwent extraoperative intracranial EEG recording and subsequent cortical resection. We computed MI, MIsv, and MItv at each electrode site during slow-wave sleep. MIsv was defined as the mean MI difference between adjacent electrode sites, whereas MItv was defined as the mean MI difference between adjacent 30-second epochs. We determined the diagnostic utility of each of the MI-related biomarkers using a summary measure referred to as "subtraction MI biomarker." This summary measure was defined as the subtraction of a given biomarker value averaged across all preserved sites from that averaged across all resected sites. Using multivariate logistic regression analysis, we tested the hypothesis that a larger subtraction MI biomarker would be associated with a better post-surgical seizure outcome, independently of the standard care variables, including clinical, seizure onset zone and MRI data. Specifically, the receiver operating characteristic (ROC) analysis determined which subtraction MI biomarker would improve the standard care variable-based model in predicting patients achieving ILAE Class-1 outcome.
Results: Ninety-five patients had an ILAE Class-1 outcome. Multivariate logistic regression analysis indicated that each of the "subtraction MI" (p = 0.016), "subtraction MIsv" (p = 0.018), and "subtraction MItv" (p = 0.011) was associated with ILAE Class-1 outcome, independently of the standard care variables. The standard care model predicted patients achieving ILAE Class-1 outcome with an area under the ROC curve (AUC) of 0.756. Adding subtraction MI, subtraction MIsv, and subtraction MItv to the standard care model improved the AUC to 0.810, 0.836, and 0.784. The DeLong test indicated that the improved AUC by subtraction MIsv was statistically significant (difference: 0.08; p = 0.011; 95% confidence interval: 0.019 to 0.142).
Conclusions: MIsv best improved the classification of postoperative seizure outcomes in this cohort of 135 patients. The epileptogenic zone may be characterized by substantial spatial instability of MI. _x000D_
Funding: NIH grant NS64033 (to E. Asano), JSPS KAKENHI Grant Number JP 22J23281 (to N. Kuroda)
Neurophysiology