Multitier Network Analysis Using Resting-State Functional MRI for Epilepsy Surgery
Abstract number :
1.257
Submission category :
5. Neuro Imaging / 5B. Functional Imaging
Year :
2021
Submission ID :
1826631
Source :
www.aesnet.org
Presentation date :
12/9/2021 12:00:00 PM
Published date :
Nov 22, 2021, 06:55 AM
Authors :
Satoshi Maesawa, MD,PhD - Dept. Neurosurgery / Nagoya Univ. Graduate School of Medicine; Epifanio Bagarinao – Nagoya University, Brain and Mind Research Center; Tomotaka Ishizaki – Dept. Neurosurgery, Nagoya University; Daisuke Nakatsubo – Dept. Neurosurgery, Nagoya University; Ryuta Saito – Dept. Neurosurgery, Nagoya University; Jun Trii – Dept. Neurosurgery, Nagoya University
Rationale: Resting-state functional MRI (rs-fMRI) has been utilized to visualize large-scale brain networks. We evaluated the usefulness of multitier network analysis using rs-fMRI in patients with focal epilepsy.
Methods: Structural and rs-fMRI data were retrospectively evaluated in 20 cases with medically refractory focal epilepsy, who subsequently underwent surgery. First, structural changes were examined using voxel-based morphometry analysis. Second, alterations in large-scale networks were evaluated using dual-regression analysis. Third, changes in cortical hubs were analyzed and the relationship between aberrant hubs and the epileptic focus was evaluated. Finally, the relationship between the hubs and the default mode network (DMN) was examined using spectral dynamic causal modeling (spDCM).
Results: Dual-regression analysis revealed significant decrease in functional connectivity in several networks including DMN in patients, although no structural difference was seen between groups. Aberrant cortical hubs were observed in and around the epileptic focus (“focus” hubs) in 85% of the patients, and strong degree of focus hubs correlated to good seizure outcomes postoperatively. In spDCM analysis, facilitation was often seen from focus hub to the contralateral side, while inhibition was seen from focus hub to nodes of the DMN.
Conclusions: Some cognition-related networks were impaired in patients with focal epilepsy. Focus hub appeared in the vicinity of epileptic focus facilitating connections to distant regions in the early phase, which may eventually generate secondary focus, while inhibiting connections to the DMN, which may cause cognitive deterioration. Our results demonstrate pathological network alterations in epilepsy and suggest that earlier surgical intervention may be more effective.
Funding: Please list any funding that was received in support of this abstract.: The Epilepsy Research Foundation (Japan); AMED(21uk1024005h0001).
Neuro Imaging