A Resting-state FMRI Study Of Brain Functional Connectivity Density In Subjects With Lumbar Disc Herniation

Objective:Combining with functional connectivity density(FCD)mapping and seed-based functional analysis method,evaluate the changes of brain functional connectivity in patients with chronic low back pain caused by lumbar disc herniation(LDH)during resting-state.Methods:Twenty two patients with lumbar disc herniation and 22 healthy controls(HC)with similar sex,age,education and handedness will be scanned with resting-state functional magnetic resonance imaging.On.the MATLAB 2014a operating platform,the RESTplus toolkit is used to process and analyze the original datas.The values of FCD in LDH group and HC group will be calculated and compared.Then,the brain regions with significant differences in FCD will be used as the region of interest(ROI),and the changes of functional connectivity between ROIs and other voxels in the whole brain will be analyzed by the seed-based approach.And the correlations between FCD values of ROIs and duration and visual analogue scale(VAS)will be analyzed.Result:(1)Compared with the HC group,the brain regions with significantly increased FCD in the LDH group include the left paracentral lobule(PCL),the right cerebellum,the left middle occipital gyrus,the left lingual gyrus,and the left precuneus.Reduced brain regions of FCD include the right dorsolateral prefrontal cortex(DLPFC),the left middle frontal orbital area,the right parietal inferior lobule.Further,seed-based approach shows that the enhancement of functional connectivity are observed between the right cerebellum and multiple brain areas,mainly including bilateral medial frontal gyrus,precuneus,lingual gyrus,and between the left middle occipital gyrus and right fusiform gyrus/left lingual gyrus/right superior parietal lobule/left PCL,and between the left precuneus and left lingual gyrus/bilateral fusiform gyrus/occipital lobe.The weakness of functional connectivity are observed between the right DLPFC and right superior temporal gyrus/right middle frontal gyrus,right inferior parietal lobule and right middle temporal gyrus/right superior frontal gyrus.(2)In LDH group,the FCD value of left lingual gyrus is positively correlated with VAS score(r=0.585,p<0.05).Conclusion:Functional connectivity changes in the brain area of LDH patients involve multiple aspects such as movement,cognition,emotion,visual,auditory and default network.Reduced functional connectivity between the right inferior parietal lobule and the right middle temporal gyrus and right superior frontal gyrus may suggest the decrease of auditory-motor integration in LDH patients,but this remains to be confirmed by further studies.The functional connectivity density value of multiple brain regions in the visual network are changed,the enhencement of functional connectivity of the visual dorsal pathway and ventral pathway,and the FCD value of the left lingual gyrus is positively correlated with the VAS score.These results suggest that the functional connectivity changes of visual network may be the image biomarkers of LDH patients.