Seizure Recurrence After TLE Surgery May Be Associated with Post-surgical Functional Connectivity Abnormality
Abstract number :
2.191
Submission category :
5. Neuro Imaging / 5B. Functional Imaging
Year :
2022
Submission ID :
2204468
Source :
www.aesnet.org
Presentation date :
12/4/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:25 AM
Authors :
Behnaz Akbarian, M.S. – Vanderbilt University; Lucas Sainburg, B.S – Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA, Vanderbilt University Institute of Imaging Science, Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA – Vanderbilt University; Baxter Rogers, PhD – Department of Radiology and Radiological Sciences – Vanderbilt University Medical Center; Dario Englot, PhD, MD – Department of Neurological Surgery – Vanderbilt University Medical Center; Victoria Morgan, PhD – Department of Radiology and Radiological Sciences – Vanderbilt University Medical Center
Rationale: Complete seizure freedom after epilepsy surgery is not obtained in all temporal lobe epilepsy (TLE) patients with medically intractable epilepsy. Understanding differences in post-surgical functional connectivity (FC) between seizure-free and non-seizure-free patients may inform how networks are related to seizure recurrence. We aimed to investigate the association between post-surgical FC and surgical outcomes compared to healthy controls in both ipsilateral and contralateral hemispheres. We hypothesized that post-surgical FC in seizure-free patients has characteristics closer to that of healthy controls than non-seizure-free patients.
Methods: A total of 27 unilateral mTLE patients (9 left, 14 males, age 40.8 ± 12.5) who underwent selective amygdalohippocampectomy (SAH) and 19 controls (7 males, age 38.5 ± 12.5) took part in this study. A T1-weighted scan (1x1x1 mm3) and resting-state fMRI (TR = 2 s, 3x3x4 mm3, follow-up duration after surgery 25.4 ± 17.3 months) were collected from control and postsurgically from patients. Two groups were identified based on the Engel outcome classification, seizure-free (13 patients, Engel Ia) and non-seizure-free (14 patients, Engel Ib-IV). Thalamus, anterior insula, posterior insula, and precuneus were selected as seeds [1]. The age-matched FC (in units of standard deviation from age-matched controls) were computed for each seed to each of 53 targets in each hemisphere. Two measures were compared to healthy controls: edge-wise FC and hemispheric asymmetry. First, seizure-free and non-seizure-free groups were compared using unpaired t-tests in each hemisphere. In those edges that were different between groups (p< 0.05, uncorrected) the means in each group determined which of those was closer to healthy control (zero). Second, asymmetric edges in each group were identified using paired t-tests between ipsilateral and contralateral edge homologues (p< 0.05, corrected for multiple comparisons). The total number of asymmetric edges in each group was computed.
Neuro Imaging