Cerebral Resting State FMRI Study In Patients With Irritable Bowel Syndrome

Objective:To explore the possible neurologic pathogenic mechanism of irritable bowel syndrome(IBS)by analyzing the imaging characteristics of the neural network structure in IBS patients using resting state fMRI.Methods:30 patients with diarrhea type IBS(IBS-D)in according to the diagnostic standard of 2006 Roman III were collected as study group,and 30 healthy volunteers with matchable gender,age,level of education,hand dominance at same time as contral group.All the subjects were underwent resting state fMRI with Siemens 3.0T superconducting MR machine,The anatomical image was got with 3D fast interference phase gradient reverse recovery(3D-FSPGR)sequence acquisition,fMRI scans were obtained using T2-plane echo imaging with gradient echo sequence(EPI-GRE).The data were preprocessed using "DPARSF" software and analyzed by "REST" software with two sample t test.Low frequency amplitude,local consistency and functional connectivity of thalamus were set as evaluation index,the difference and correction of index were made between IBS group and healthy control group.Results:1.ReHo value comparison:By comparison with healthy controls,IBS patients with reduced ReHo regions included bilateral anterior cingulate,frontal lobe and left insula;increased areas included the right frontal orbital gyrus,bilateral temporal lobe,bilateral occipital lobe and bilateral cerebellar posterior lobe(double sample t test,P<0.001,after correction).2.ALFF value comparison:Compared with the healthy control group,the brain areas in IBS group exhibiting enhanced ALFF included bilateral thalamus,right hippocampus,left parahippocampal gyrus,bilateral inferior parietal gyrus,right cerebellar anterior lobe,cerebellar vermis,bilateral inferior occipital gyrus,left middle parietal gyrus,and exhibiting weakened ALFF included bilateral frontal lobe,left anterior cingulate gyrus,right insula(double sample t test,P<0.001,after correction).3.Thalamic functional connectivity:In IBS group,posterior cingulate and bilateral anterior thalamic nuclei showed enhanced functional connectivity,while left cuneus showed weakening connection comparing with control group(double sample t test,P<0.01,after correction).Conclusion:On resting state fMRI,pain management related brain and brain network in IBS are dysfunction,which perhaps involve the pathogenesis of IBS,and is helpful to the further study.