Aberrant Brain Functional Connectivity In Patients With Obstructive Sleep Apnea-hypopnea Syndrome:A Functional Magnetic Resonance Imaging Study

Part ?Resting state functional connectivity changes in patients with obstructive sleep apnea-hypopnea syndrome:resting-state functional MRI studyObjective To investigate the change of default mode network(DMN)in subjects with obstructive sleep apnea-hypopnea syndrome(OSAHS)using resting-state functional connectivity(rsFC).Methods resting-state functional magnetic resonance imaging(rs-fMRI)data were collected from twenty-nine subjects with OSAHS and twenty-six normal controls.The data were analyzed with the rsFC method and compared between OSAHS and controls.Z-value of abnormal rsFC in different brain regions were correlated with clinical variables including apnea-hypopnea index(AHI),oxygen desaturation index(ODI),epworth sleepniess scale(ESS),rey-osterrieth complex figure test(CFT-immediately),CFT-delay,logical memory test-immediately(LMT-immediately),LMT-delay and MMSE(minimum mental state examination).Results The rsFC showed significant increase in left temporal cortex,right midfrontal cortex,left precuneus cortex and decrease in bilateral inferior parietal lobule(IPL),left medial prefrontal cortex(MPFC),left superior frontal cortex and right cerebellum in patients with OSAHS.FC strength in the left precuneus showed a remarkable positive correlations with ODI(r =0.399,p = 0.032)and CFT-delay scores(r = 0.378,p = 0.043).We found FC strength in the right cerebellum was positively correlated with the CFT-delay scores(r = 0.441,p = 0.017).FC strength in the right cerebellum and left IPL demonstrated a remarkable positive correlation with LMT-delay scores(r = 0.389,p = 0.037;r = 0.379,p = 0.043),respectively.Meanwhile there was a strong negative correlation between left MPFC region and ESS scores(r =-0.398,p = 0.032).Conclusion The abnormal rsFC in subjects with OSAHS indicated the compensatory change of brain function,which possibly giving an innovative approach and perspective on understanding the neural mechanism alteration of OSAHS-related cognition.Part ?Aberrant interhemispheric functional connectivity in patients with obstructive sleep apnea-hypopnea syndromeObjective To explore the change of interhemispheric functional coordination in patients with obstructive sleep apnea-hypopnea syndrome(OSAHS)applying a novel voxel-mirrored homotopic connectivity(VMHC)method.Methods 29 patients with OSAHS and 26 sex-,gender and eduction-comparable normal controls were recruited and obtained resting-state functional magnetic resonance imaging(rs-fMRI)data.We employed VMHC method to analyze the interhemispheric functional connectivity difference between OSAHS and healthy controls.Z-value of altered VMHC in different brain regions were correlated with clinical characteristics.Results The VMHC revealed significant increase in bilateral calcarine and precuneus in OSAHS patients compared to normal controls.Futhermore,there were significantly positive correlations between AHI and VMHC coefficients of calcarine and precuneus(r = 0.399,p = 0.032;r = 0.378,p = 0.043),respectively.However,there were no correlations between VMHC and ODI,MMSE,CFT,LMT,ESS.Conclusion The abnormal VMHC associated with clinical variables in OSAHS patients might give new insights into the neural pathophysiology that underlie the OSAHS-related cognitive deficits.