Several studies using state-of-the-art imaging techniques have revealed that juvenile myoclonic epilepsy, a form of epilepsy that starts in childhood or adolescence, might be associated with microstructural and functional changes in several brain regions. In fact, these abnormalities have been found not only the thalamofrontal network, but also in temporal and parieto-occipital areas.
To further understand these findings, scientists from the Catholic University of Korea investigated structural alterations beyond the thalamofrontal system, searching for integrated changes in white matter, cortical gray matter, and subcortical structures. The study included 18 juvenile myoclonic epilepsy patients and 22 healthy controls.
The team used DTI scans to analyze white matter modifications and surface analysis to clarify gray matter characteristics. They found that when compared to healthy participants, the epilepsy patients had reduced fractional anisotropy and increased mean diffusivity, values that describe changes in water diffusion in the brain. Epileptic subjects also showed a significant decrease in gray matter thickness in temporoparietal regions, areas of the brain where the temporal and parietal lobes meet.
From sequential oblique coronal T1-weighted MRI scans, Analyze software was used to manually outline regions of interest such as the coronal hippocampus, the thalamus, and the intracranial cavity contour. Manual volumetry analysis provided a great deal of specificity and precision compared to other automated measuring methods. Juvenile myoclonic epilepsy patients exhibited substantial reduction in thalamic and hippocampal volumes. While atrophy of the thalamus has long been reported in the literature, the reduction in hippocampal volume encountered by the group may support the involvement of this and other temporal structures in juvenile myoclonic epilepsy.
Results from this study highlight how structural abnormalities in this condition may involve the limbic and temporoparietal regions and not be confined to well-known thalamofrontal areas of the brain. As the mechanism or cause of these structural changes is still unclear, future studies of functional connectivity and brain activity may help better understand these novel findings.Brain Studies, Epilepsy