Altered whole brain functional connectivity in patients with minimal hepatic encephalopathy: a resting-state functional MRI study

Abstract

Objective To investigate the alteration of the whole brain functional connectivity in patients with minimal hepatic encephalopathy(MHE) by using resting-state functional MRI,and to explore its role in distinguishing the MHE from cirrhotic patients without MHE by using the receiver operator characteristic(ROC) curve.Methods Thirty cirrhotic patients with MHE,32 cirrhotic patients without MHE (non-MHE),and 49 healthy controls underwent standard resting-state functional MRI scan.Whole brain functional connectivities were compared with analysis of variance test to observe the difference among three groups,and then compared with Post-hoc test to investigate the changes between MHE and non-MHE groups.Results There were widespreadly different functional connectivities among three groups.All 115 functional conenctivities showed significant difference among three groups(all P＜0.05).Compared with non-MHE patients,MHE patients showed 6 decreased functional connectivity in the following brain regions (P＜0.05):between left supper temporal gyrus-right orbitofrontal cortex,left Heschl's gyrus-left Rolandic operculum,left Heschl's gyrus-right olfactory cortex,left hippocampus-right amygdala,left putamen-right putamen,and left temporal pole of supper temporal gyrus-right temporal pole of middle temporal gyrus (t=-4.41-3.82,P＜0.01).ROC analysis demonstrated that the left hippocampus-right amygdala had the highest value for differentiating MHE from non-MHE group(AUC=0.78,95％CI 0.66-0.90) with a cutoff value=0.56,sensitivity=73％ and specificity=81％).Conclusion Functional connectivity analysis can be used to observe the functional changes in MHE patient,and has a potential for the early diagnosis of MHE. Key words: Hepatic encephalopathy ; Magnetic resonance imaging; Neural networks(computer)