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Updated: Jun 3, 2026
Anteromesial Temporal Lobectomy for Medically Intractable Temporal Lobe Epilepsy: An Operative Study
Published on: August 15, 2025
Neocortical thinning in "benign" mesial temporal lobe epilepsy
Angelo Labate1, Antonio Cerasa, Umberto Aguglia
1Institute of Neurology University Magna Graecia, Catanzaro, Italy. labate@unicz.it
Purpose:
In refractory mesial temporal lobe epilepsy (MTLE) extrahippocampal and neocortical abnormalities have been described in patients with or without mesial temporal sclerosis (MTS). Recently we observed gray matter reductions in regions outside the hippocampus in benign MTLE with or without MTS. Cortical thickness has been proposed as a viable methodologic alternative for assessment of neuropathologic changes in extratemporal regions. Herein, we aimed to use this technique to describe cortical abnormalities in patients with benign TLE.
Methods:
Whole-brain cortical thickness analysis (FreeSurfer) was performed in 32 unrelated patients with benign TLE [16 patients with signs of MTS on magnetic resonance imaging (MRI), pMTLE; 16 without, nMTLE] and 44 healthy controls.
Key Findings:
In the pMTLE group, the most significant thinning was found in the sensorimotor cortex bilaterally but was more extensive in the left hemisphere (false discovery rate, p < 0.05). Other areas were localized in the occipital cortex, left supramarginal gyrus, left superior parietal gyrus, left paracentral sulcus, left inferior/middle/superior frontal gyrus, left inferior frontal sulcus, right cingulate cortex, right superior frontal gyrus, right inferior parietal gyrus, right fusiform gyrus, and cuneus/precuneus. In the nMTLE, a similar neurodegenerative pattern was detected, although not surviving correction for multiple comparisons. Direct comparison between pMTLE and nMTLE did not reveal significant changes.
Significance:
Patients with either benign pMTLE or nMTLE showed comparable cortical thinning, mainly confined to the sensorimotor cortex. This finding that is not appreciated on routine MRI supports the hypothesis that similar to refractory MTLE, even in benign MTLE, pathology in neocortical regions maybe implicated in the pathophysiology of this syndrome.
Insights
Benign mesial temporal lobe epilepsy (MTLE) involves cortical thinning, particularly in the sensorimotor cortex, even without mesial temporal sclerosis (MTS). This suggests neocortical involvement in benign MTLE pathophysiology.
Area of Science:
- Neurology
- Neuroimaging
- Epilepsy Research
Background:
- Refractory mesial temporal lobe epilepsy (MTLE) is associated with extrahippocampal and neocortical abnormalities.
- Gray matter reductions outside the hippocampus have been observed in benign MTLE, with or without mesial temporal sclerosis (MTS).
- Cortical thickness analysis offers a method for assessing neuropathologic changes in extratemporal regions.
Purpose of the Study:
- To investigate cortical abnormalities in benign MTLE using cortical thickness analysis.
- To describe the pattern of cortical thinning in patients with benign MTLE, differentiating between those with (pMTLE) and without (nMTLE) signs of MTS.
Main Methods:
- Whole-brain cortical thickness analysis was performed using FreeSurfer software.
- The study included 32 unrelated patients with benign MTLE (16 pMTLE, 16 nMTLE) and 44 healthy controls.
Main Results:
- Significant cortical thinning was observed bilaterally in the sensorimotor cortex in the pMTLE group, more pronounced in the left hemisphere.
- Additional areas of thinning in pMTLE included the occipital cortex, left supramarginal and superior parietal gyri, left frontal regions, right cingulate and superior frontal gyri, right inferior parietal gyrus, right fusiform gyrus, and cuneus/precuneus.
- A similar pattern of neurodegeneration was noted in the nMTLE group, though not statistically significant after multiple comparison correction. No significant differences were found between pMTLE and nMTLE groups.
Conclusions:
- Patients with benign MTLE, regardless of MTS presence, exhibit comparable cortical thinning, primarily in the sensorimotor cortex.
- These findings, not apparent on routine MRI, support the hypothesis of neocortical involvement in the pathophysiology of benign MTLE, similar to refractory MTLE.
