Abstract
Background
MRI-negative TLE (TLE-N) is a manifestation lacks visible MRI findings yet with detectable electrophysiological changes. In this study, differences of gray matter in drug-controlled MRI negative temporal lobe epilepsy (cTLE-N) and drug-resistant MRI negative temporal lobe epilepsy (rTLE-N) patients were calculated and analyzed by voxel-based morphology (VBM) and surface-based morphology (SBM), to discover the brain structural changes of TLE-N patients.
Materials and methods
Consecutive resident patients with 30 cTLE-N and 21 rTLE-N were recruited into respective groups, and 30 healthy controls’ structural MRI (sMRI) data collected as a control group. Open-source software based on VBM and SBM was deployed as gray matter volume (GMV) and cortical thickness (CT) analytic tools.
Results
VBM analysis showed that GMV of bilateral thalamus and right lingual gyrus of cTLE-N group, and left hippocampus, left fusiform gyrus and left thalamus of rTLE-N group were smaller compared to HC group(FDR corrected, P<0.05), while right cerebellum, inferior temporal gyrus, hippocampus, parahippocampal gyrus, amygdala, fusiform gyrus, orbital middle frontal gyrus, and left posterior central gyrus in cTLE-N group, and bilateral cerebellum and middle temporal gyrus, right fusiform gyrus, amygdala, hippocampus, and left middle occipital gyrus of rTLE-N group were greater than HC group(FDR corrected, P<0.05). SBM analysis showed that CT of the left medial orbitofrontal cortex and lateral occipital cortex in cTLE-N group, and thickness of the left medial orbitofrontal, temporal pole, middle temporal gyrus and right anterior superior cingulate cortex in rTLE-N group were thinner, compared to HC group. Correlation analysis showed that GMV and CT of different structures were correlated with age of onset, disease duration, and MoCA score.
Conclusion
This study utilized two different sMRI analytic tools and discovered several brain morphological changes in TLE-N. These morphological changes were also correlated with clinical variables. Further study may indicate the potential of these findings on the recognition of the TLE-N epilepsy network.
A Lighter Shade of Gray: Is Temporal Lobe Epilepsy a Progressive Gray Matter Disorder?
