Elevated Brain Temperature in People with Idiopathic Generalized Epilepsy Compared to Healthy Adults
Abstract number :
2.457
Submission category :
5. Neuro Imaging / 5A. Structural Imaging
Year :
2022
Submission ID :
2233032
Source :
www.aesnet.org
Presentation date :
12/4/2022 12:00:00 PM
Published date :
Nov 22, 2022, 05:29 AM
Authors :
Brandon Mitchell, BS – University of Alabama at Birmingham; Ayushe Sharma, PhD Candidate – Graduate Trainee, Department of Neurology, University of Alabama at Birmingham; Rodolphe Nenert, PhD – Research Associate, Department of Neurology, University of Alabama at Birmingham; Jerzy Szaflarski, MD, PhD – Professor, Department of Neurology, University of Alabama at Birmingham; Jane Allendorfer, PhD – Assistant Professor, Department of Neurology, University of Alabama at Birmingham
This is a Late Breaking abstract
Rationale: Whole-brain magnetic resonance spectroscopy and thermometry (MRSt) with echo-planar sequence imaging (EPSI) may be a promising tool for non-invasive assessment of brain temperature as a proxy for neuroinflammation in neurological disorders. Brain temperature estimation is based on the chemical shift difference between water (H2O) and creatine (CRE). Epilepsy is considered a network disorder, and MRSt-EPSI measurements may be indicative of neuroinflammation that occurs in epilepsy. To date, MRSt-EPSI has not been used to estimate brain temperature in people with idiopathic generalized epilepsy (IGE). Since presumably there is no focal source of seizures in IGE, we hypothesized that compared to healthy adults (HA), people with IGE will have increased brain temperature in widespread brain regions.
Methods: Participants (9 HA, 9 IGE) were scanned on a 3T Prisma scanner with a 20-channel head coil. T1-weighted anatomical images and whole-brain MRSt-EPSI images were acquired. The Metabolite Imaging and Data Analysis System software was used for image reconstruction and spectral processing, including spatial reconstruction, frequency alignment, B0 inhomogeneity correction, co-registration between EPSI and T1-wieghted images, AAL2 atlas registration, lipid suppression, spectral fitting, normalization, and integration with reference water molecules. Voxel-wise brain temperature was calculated [TCRE = (-102.61 x DH2O-CRE) + 206.1°C] while correcting for the difference between grey and white matter signal intensities.
Results: HA and IGE were matched for age [p = 0.877] and sex [p = 0.681]. An independent-samples t-test (IGE > HA) showed that global TCRE for IGE [M = 37.62°C, SD = 0.71°C, Range = 36.34°C-39.27°C] was significantly higher than for HA [M = 37.39°C, SD = 0.29°C, Range = 36.74°C-37.83°C], t = 2.01, p = 0.024, R2 = 0.062. A voxel-wise independent-samples t-test (IGE > HA) identified significantly higher TCRE in IGE patients compared to HA in the right medial orbitofrontal gyrus [cluster extent = 40 voxels; centroid at x = 20, y = 24, z = -22; t = 18.93, pFWE-corr < 0.001] and the left inferior frontal gyrus [cluster extent = 10 voxels; centroid at x = -14, y = 10, z = -18; t = 14.84, pFWE-corr = 0.002] (Figure 1).
Conclusions: People with IGE express significantly higher TCRE than HA overall, and specifically in orbitofrontal and fronto-basal cortical regions. This study demonstrates the feasibility of using MRSt to identify areas of elevated brain temperature as a possible proxy for measuring neuroinflammation in people with IGE. Future studies with larger sample sizes that couple MRSt with other measures of central and peripheral inflammation are needed to confirm our results.
Funding: This work was supported by NIH R01HD102723 to JBA, the State of AL General Fund (Carly’s Law) to JPS, and the UAB Epilepsy Center.
Neuro Imaging