Study Of Resting-state Functional Magnetic Resonance Imaging For Intractable Epilepsy With Conventional MRI-negative

Objective:To investigate the functional connectivity strength（FCS）of conventional MRI-negative intractable epilepsy（ITE）in children using resting-state functional magnetic resonance imaging（rs-fMRI）,and compare whether there was a difference between intractable group and non-intractable group in FCS,analyzing the correlation between changes of FCS and intelligence quotient（IQ）.Methods:Twenty-eight children with ITE were recruited from the pediatric outpatient of the affiliated hospital of Zunyi Medical University from October 2018 to December 2019（Intractable epilepsy was diagnosed by pediatricians above deputy director according to the ILAE 2010 consensus）.13 cases with organic disease were excluded,15 cases were included,and 24 children with non-intractable epilepsy were recruited.At the same time,25 healthy volunteers with matching gender,age,and educational level were recruited as control group.Children with ITE were tested for intelligence by using Chinese Wechsler Intelligence Scale for Children.All subjects underwent brain MRI examination with GE3.0T HDxt MRI scanner.T₂-FLAIR and rs-fMRI data were collected successively.The rs-fMRI data was preprocessed by using DPARSF V4.2.First,the differences of FCS values were evaluated among the three groups.A one-way analysis of covariance（ANCOVA）was performed in a voxel-wise manner in the whole brain using SPM8,age,gender and education level as covariates,and then the three groups were compared in pairs.The differences of FCS values among the three groups were compared by using a threshold at p<0.05 with Bonferroni correction.The correlation between FCS values in the abnormal brain areas of intractable group and IQ were analyzed and evaluated,p<0.05 was considered statistically significant.Results:The intractable group,the non-intractable group and the control group had no statistical difference in age,gender and educational level（p>0.05）.The variance analysis of resting-state FCS was statistically different among the three groups（p<0.05,Bonferroni correction）.Compared with the normal control group,the intractable group showed decreased FCS values in right precentral gyrus,right temporal pole of superior temporal gyrus,right middle temporal gyrus,right temporal pole of middle temporal gyrus,left paracentral lobule and bilateral precuneus,and increased FCS values in left triangular inferior frontal gyrus,left parahippocampal gyrus,left caudate nucleus,left supplementary motor area,right postcentral gyrus,right calcarine fissure and surrounding cortex and midbrain（p<0.05,Bonferroni correction）.Correlation analysis showed that FCS values in left caudate nucleus were positively correlated with verbal intelligence quotient（r_s=0.599,p=0.026）.Compared with the non-intractable group,the intractable group displayed decreased FCS values in right medial superior frontal gyrus,left inferior temporal gyrus and bilateral fusiform gyrus,and increased FCS values in right middle temporal gyrus,right inferior temporal gyrus,right middle occipital gyrus,right calcarine fissure and surrounding cortex（p<0.05,Bonferroni correction）.Compared with the normal control group,the non-intractable group showed decreased FCS values in bilateral middle temporal gyrus,right orbital superior frontal gyrus,right supplementary motor area,right superior frontal gyrus,left cuneus and right precuneus,and increased FCS values including bilateral fusiform gyrus,bilateral parahippocampal gyrus,bilateral caudate nucleus,left temporal pole of middle temporal gyrus,left thalamus,left lingual gyrus,right triangular inferior frontal gyrus,right middle frontal gyrus（p<0.05,Bonferroni correction）.Conclusion:There were abnormalities in FCS of multiple brain regions in children with ITE,moreover,it was found that the left caudate nucleus FCS were related to verbal intelligence quotient,which providing imaging basis for cognitive function and pathophysiological mechanism of ITE.