Abstracts

Rationale: The hallmark of mesial temporal sclerosis (MTS) is neuronal loss and gliosis the hippocampus and related structures, but brain atrophy and tissue damage have been described far from temporal lobe. Several studies have reported changes in size and cortical thinning in frontal and parietal regions. Evaluating whole brain cortical changes is important for understanding the mechanism of injury. In this study we used the FreeSurfer package to find cortical thickness differences between patients and normal controls. Methods: 135 patients with MTS and 105 normal controls were studied with one 1.5 Tesla MRI equipment (Magneton Vision Plus, Siemens, Erlanger, Germany). In addition to a standard epilepsy protocol, one MPRAGE T1-weighted whole brain sequence with isotropic 1mm voxel was acquired for each subject. The images were processed and analyzed using FreeSurfer package version 4.5 and Qdec version 1.2. Results: We found significant cortex thinning in the temporal lobe mostly in inferior temporal gyrus and entorhinal cortex, in the frontal lobe (lateral orbitofrontal cortex, medial orbitofrontal cortex, middle frontal gyrus and superior frontal gyrus), in the parietal lobe (post-central gyrus), and in the lingual gyrus of the occipital lobe. Conclusions: These confirm the hypothesis that tissue damage occurs far from temporal lobe in TLE, and the pathological process includes cortical thickness reduction probably related to temporal lobe network.