Objective This study aimed to explore the changes of interhemispheric functional homotopy in patients with different course of temporal lobe epilepsy based on voxel-mirrored homotopic connectivity(VMHC).Methods Twenty temporal lobe epilepsy patients with a short disease course(TLE-SD),twenty-seven temporal lobe epilepsy patients with a long disease course(TLE-SD)and thirty healthy controls(HC)matched with demo-graphic data were enrolled.All participants finished functional MRI scans and neuropsychological assessment.Brain regions with significant changes between the TLE-SD/TLE-LD group and the healthy controls group were obtained based on the VMHC analysis,and the two-samples t-test was performed in the different brain regions of VMHC values between the two comparisons.The VMHC values of abnormal brain regions in the patient group were extracted and used for correlation analysis with the scale scores.Results Compared with HC,the VMHC values of the putamen and anterior cingulate gyrus were reduced in the TLE-SD group,while the VMHC values of the putamen,anterior cingulate gyrus,superior temporal gyrus and superior frontal gyrus were reduced in the TLE-LD group.Compared with the TLE-SD group,the VMHC values of the superior temporal gyrus in the TLE-LD group was significantly reduced(t=2.918,P=0.033).Correlation analysis showed that the VMHC values of the putamen was positively correlated with the Montreal Cognitive Assessment(MoCA)scores(r=0.442,P=0.021).Conclusions The interhemispheric functional homotopy was impaired in patients with temporal lobe epilepsy and the impairment may be more severe in patients with a long course of disease.Cognitive impairment in patients with temporal lobe epilepsy may be related to the abnormalities of interhemispheric functional homotopy.

Objective:To study the neural mechanism between abnormal brain functional activity and alertness function in temporal lobe epilepsy (TLE) patients with or without hippocampal sclerosis.Methods:A total of 21 TLE patients with hippocampal sclerosis (TLE-HS), and 18 TLE patients without hippocampal sclerosis (TLE-N) diagnosed in the Department of Neurology of the First Affiliated Hospital of Guangxi Medical University from May 2016 to November 2022 and 28 healthy controls (HC) matched with demographic data were recruited.All the 67 participants completed the attention network test (ANT) and resting-state fMRI (rs-fMRI) scans. The REST software was used to analyze fractional amplitude of low-frequency fluctuation (fALFF) and functional connectivity (FC) based on one-way ANOVA in order to obtain differential brain regions in abnormal spontaneous neuronal activity and functional connectivity among the three groups. The SPSS 26.0 software was used to analyze the correlation between fALFF/FC values in differential brain regions and alertness network efficiency by Pearson correlation analysis.Results:There was a significant difference in the alerting network effect among the three groups ( F=4.621, P=0.013), and the post-hoc analysis showed that the alerting network effect in the TLE-HS group((59.40±22.85)ms)was significantly higher than that in the HC group((38.85±21.08)ms)(Bonferroni correction, P=0.017). The fALFF analysis showed that the fALFF values of the right superior frontal gyrus in the TLE-HS group (0.16±0.52) and the TLE-N group (0.49±0.51) were significantly lower than that in the HC group (1.01±0.46), while the fALFF values of the left precentral gyrus in the TLE-HS group (0.60±0.55) was significantly higher than that in the TLE-N group (-0.19±0.51) and the HC group (-0.15±0.36) (Bonferroni correction, all P<0.05). The functional connectivity analysis revealed that the FC values between the left inferior frontal gyrus and the right superior frontal gyrus in the TLE-HS group (0.11±0.16) and TLE-N group (0.02±0.19) were significantly higher than those in the HC group (-0.18±0.18). The FC values between the right supramarginal gyrus and the right superior frontal gyrus in the TLE-HS group (0.10±0.21) were significantly higher than those in the HC group (-0.18±0.16). The FC values between the left supplementary motor area and the right superior frontal gyrus in the TLE-HS group (0.20±0.21) were significantly higher than those in the TLE-N group (-0.03±0.31) and the HC group (-0.10±0.15) (Bonferroni correction, all P<0.05). The correlation analysis showed that the FC values between the left supplementary motor area and the right superior frontal gyrus in the TLE-HS group were significantly positively correlated with alertness network efficiency ( r=0.436, P=0.048). Conclusions:There are abnormal spontaneous neuronal activity and brain functional connectivity in TLE patients with or without hippocampal sclerosis, and the abnormality is more pronounced in the TLE-HS group. The abnormal brain functional connectivity may play an essential role in alertness dysfunction.

Objective:To explore the changes in topological attributes of structural covariance network based on cortical thickness and the brain functional activities in patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis by graph theory and functional connectivity (FC) analyses, and to investigate whether these changes were correlated to cognitive impairment.Methods:A total of 33 patients with anti-NMDAR encephalitis from Department of Neurology of the First Affiliated Hospital of Guangxi Medical University(patient group) and 35 healthy controls(control group) with matched gender, age, and education were included from July 2018 to November 2021.All subjects received cognitive function assessments, structural and functional magnetic resonance imaging scans.Structural covariance networks were constructed in the two groups based on cortical thickness values and topological characteristics of networks were computed.A non-parametric permutation test which repeated 1 000 times was used to compare the characteristics of the networks between the two groups.Brain regions with abnormal topology were defined as region of interest(ROI), and FC values in global brain level were calculated.SPM 12 and RESTplus were used to identify the brain regions with significant differences in FC values between the two groups.Finally, Spearman correlation analysis between FC values of significant brain regions and cognitive scores were performed by SPSS 24.0.Results:The cognitive score of patients with anti-NMDAR encephalitis (27.0(23.5, 28.0)) was lower than that in control group(29.0(27.0, 30.0)) ( Z=-3.029, P=0.002). Graph theory analysis found that the patients showed significantly increased clustering coefficients ( P=0.004) and decreased global efficiency ( P=0.004) compared with healthy controls.Moreover, the nodal efficiency of left ventral posterior cingulate cortex (vPCC) and right dorsal posterior cingulate cortex (dPCC), as well as the nodal degree centrality of left vPCC and left polar planum of superior temporal gyrus (ppSTG) in patient group were significantly decreased ( P<0.05, FDR corrected) compared with control group.FC analysis showed the increased FC values between left vPCC and posterior cerebellum (MNI: x=6, y=-66, z=-21), as well as between left ppSTG and anterior cerebellum (MNI: x=6, y=-54, z=-12) (GRF corrected, voxel level P<0.001, cluster level P<0.05) in patient grooup.The FC values between left vPCC and posterior cerebellum were negatively correlated with the cognitive scores ( r=-0.403, P=0.020). Conclusion:Patients with anti-NMDAR encephalitis show abnormal topology of structural covariance network based on cortical thickness and altered FC values, some of which are correlated to cognition and may be the underlying neural mechanism of cognitive impairment in patients with anti-NMDAR encephalitis.