Long-and short-range functional connectivity density alteration in non-alcoholic cirrhotic patients one month after liver transplantation: A resting-state fMRI study

PURPOSE: To longitudinally evaluate long- and short-range functional connectivity density (FCD) alteration in cirrhotic patients one month after liver transplantation (LT) and their correlation with cognitive changes by using resting-state functional magnetic resonance imaging (rs-fMRI). METHODS: Twenty seven candidates awaiting LT and 24 age-, gender-, and education-matched healthy controls (HCs) were studied. All 27 patients and HCs performed rs-fMRI examinations. Of 27 cirrhotic patients, 13 patients received LT underwent the repeated rs-fMRI examinations one month after LT. Laboratory and psychometric tests were carried out. The long- and short-range FCD maps derived from degree centrality calculation were compared. Correlations between FCD alteration and laboratory/psychometric changes were evaluated as well. RESULTS: In cirrhotic patients, most of the brain areas with altered long- and short-range FCD could reverse one month after LT, which was accompanied with cognitive and liver functional improvement. The reduced long-range FCD in right posterior cingulate cortex (PCC) and Left middle frontal gyrus (MFG), and reduced short-range FCD in right precuneus (PCu) persisted in the early period after LT. In addition, one month after LT, the post-LT group showed reduced long-range FCD in right rectus gyrus (REC) and left medial prefrontal cortex (MPFC), and reduced short-range FCD in left middle temporal gyrus (MTG), when compared with the pre-LT group. We found Δdigital symbol test (ΔDST) score positively correlated with long-range ΔFCD in right precentral gyrus (preCG) (r = 0.72, P < 0.01) and right supplementary motor area (SMA) (r = 0.59, P < 0.05). CONCLUSION: LT results in favorable effect on cognitive function in cirrhotic patient, which can be reflected by FCD alteration. However, persistence of PCC/PCu functional connectivity disturbance one month after LT indicates complete cognitive function restoration may need a longer time.