Preliminary Study Of Frontal Lobe Epilepsy Based On Resting-state Functional MRI

Part1:The focal brain activity changes in frontal lobe epilepsyObjective To study the change of brain activity in frontal lobe epilepsy, and explore its pathological physiological mechanism in frontal lobe epilepsy.Methods Using amplitude of low frequency fluctuation (ALFF) analysis of resting state functional magnetic resonance imaging (fMRI),46 cases of structural MRI-negative frontal lobe epilepsy (FLE) patients with 46 normal controls were studied. The difference of ALFF between FLE patients and controls were analysed with 2-sample test. Then the correlation between ALFF and epilepsy duration of FLE by voxel-based algorithm were investigated.Results Compared with the controls, FLE patients presented increased ALFF in bilateral mesial frontal lobe, insula, thalamus and basic ganglia, while decreased ALFF in both inferior temporal gyrus. Correlation analysis showed that ALFF in bilateral mesial frontal lobe, insula, and basic ganglia positively correlated with epilepsy duration.Conclusion The funtion of mesial frontal lobe, insula, thalamus and basic ganglia altered in FLE patients. And amplitude of low frequency fluctuation (ALFF) analysis of resting state functional magnetic resonance imaging provides a reliable tool for structural MRI-negative frontal lobe epilepsy.Part2:Altered regional and distant functional connectivity in frontal lobe epilepsyObjective With functional magnetic resonance imaging (fMRI), we have explored the relationship between brain activation and functional connectivity in a cohort of patients with cryptogenic FLE and healthy controls. The aims of this study were to assess the altered regional and distant functional connectivity by using resting-state fMRI in patient with cryptogenic FLE.Methods 46 young adult patients of FLE who showed no abnormalities in conventional structural MRI, and 46 healthy control volunteers were recruited for the study. Resting state functional MRI was performed on a 3T MR scanner. ReHo (regional homogeneity) and seed-based correlation functional connectivity (FC) were used to characterize brain regions changes. Their associations with disease duration were performed.Results Both methods revealed network disturbances in patients with FLE. Compared with normal controls, FLE patients presented increased ReHo in anterior cingulate, middle cingulate, insula, thalamus and basic ganglia, while decreased ReHo in both inferior temporal gyrus. Seed-based FC analysis revealed that decreased connectivities were found within the frontal lobe as well as extrafrontal structures.Conclusion Patients with FLE showed decreased functional connectivity in a specific subset of frontal lobe connections. These include connections between different frontal lobe areas, as well as connections to distant brain areas..Impairment in functional connectivity was associated with epilepsy duration.This may be the diffuse disruptive effect of long-term injurious effects of FLE.