Functional Connectivity Density And Functional Connectivity Of Default Mode Network And Frontoparietal Network Alterations At Resting State In Neuromyelitis Optica Spectrum Disorders Patients

Objective Using a novel functional connectivity density?FCD?approach to investigate the strength of intrinsic connectivities alternations in neuromyelitis optica spectrum disorders?NMOSD?patients at resting-state,and the correlations with clincal scores and duration.To evaluate the difference of brain default mode network?DMN?and frontoparietal network?FPN?connectivity of NMOSD by using independent component analysis?ICA?,and their correlations with clincal scores.Methods A total of 20 NMOSD patients?NMOSD group?and 20 sex-and age-matched healthy controls?control group?underwent resting-state functional MRI?rs-fMRI?examinations.Data of rs-fMRI were measured on DPARSFA?based on Matlab station?by using degree centrality method?threshold value 0.25?.Analysis of FCD map between the patient group and the control group were performed by two sample t test.Correlation analysis was performed for regions with FCD value statistically different in NMOSD with clinical parameters.Twenty NMOSD patients and twenty healthy controls underwent rest-state fMRI data were analyzed by using GIFT software,and the differences of functional connectivity?FC?between the two groups were compared by SPM8 software.The correlations between altered parameters of FC and expanded disability status scale?EDSS?scores,disease duration were further explored using the Pearson correlation coefficients.Results Compared with the control group,NMOSD patients showed significantly increased FCD in the left cerebelum_crus and decreased FCD in the bilateral frontal lobe?BA 11?,bilateral cerebelum₆ and left lingual gyrus.Moreover,the FCD values of the left cerebelum_crus was correlated with duration?r = 0.6,P = 0.005?.Compared with the control group,the FC score of DMN in NMOSD group significantly decreased in the right middle frontal cortex and right middle occipital cortex,while increased in bilateral lingual gyrus,extended to right superior parietal lobule and left supplementary motor area;the FC score of FPN decreased in bilateral cuneus cortex,while no FC score increased area.In addition,the FC score changes of right lingual gyrus correlated with disease duration.Conclusion NMOSD patients have abnormal brain function network connection properties,which show that the increase or decrease of FCD in multiple brain functional areas may be related to the neuropathologic mechanism of the limb and cognitive dysfunction of NMOSD patients.The FC abnormalities in DMN and FPN in NMOSD patients may provide the evidence that the spinal cord and optic neuritis caused not only corresponding clincal symptoms but also brain hidden and widespread damage.Altered functional changes in multiple brain regions may caused by the secondary spinal cord lesions of retrograde sensorimotor cortex lesions,demonstrate that the brain functional network is a complex interconnected network with both the process of damage and compensation.