Altered Regional Homogeneity in the Development of Minimal Hepatic Encephalopathy: A Resting-State Functional MRI Study

Abstract

BackgroundLittle is known about how spontaneous brain activity progresses from non-hepatic encephalopathy (non-HE) to minimal HE (MHE). The purpose of this study was to evaluate the evolution pattern of spontaneous brain activities in cirrhotic patients using resting-state fMRI with a regional homogeneity (ReHo) method.Methodology/Principal FindingsResting-state fMRI data were acquired in 47 cirrhotic patients (minimal HE [MHE], n = 20, and non-HE, n = 27) and 25 age-and sex-matched healthy controls. The Kendall’s coefficient of concordance (KCC) was used to measure the regional homogeneity. The regional homogeneity maps were compared with ANOVA tests among MHE, non-HE, and healthy control groups and t-tests between each pair in a voxel-wise way. Correlation analyses were performed to explore the relationships between regional ReHo values and Child-Pugh scores, number connection test type A (NCT-A), digit symbol test (DST) scores, venous blood ammonia levels. Compared with healthy controls, both MHE and non-HE patients showed decreased ReHo in the bilateral frontal, parietal and temporal lobes and increased ReHo in the bilateral caudate. Compared with the non-HE, MHE patients showed decreased ReHo in the bilateral precuneus, cuneus and supplementary motor area (SMA). The NCT-A of cirrhotic patients negatively correlated with ReHo values in the precuneus, cuneus and lingual gyrus. DST scores positively correlated with ReHo values in the cuneus, precuneus and lingual gyrus, and negatively correlated with ReHo values in the bilateral caudate (P<0.05, AlphaSim corrected).Conclusions/SignificanceDiffused abnormal homogeneity of baseline brain activity was nonspecific for MHE, and only the progressively decreased ReHo in the SMA and the cuneus, especially for the latter, might be associated with the development of MHE. The ReHo analysis may be potentially valuable for detecting the development from non-HE to MHE.

Altered Pattern of Spontaneous Brain Activity in the Patients with End-Stage Renal Disease: A Resting-State Functional MRI Study with Regional Homogeneity Analysis

“…The pattern of resting-state brain activities obtained by the ReHo method is very similar to that observed by PET in healthy individuals, which indicates that ReHo is a promising measurement for the resting-state local brain activities [18]. ReHo has been successfully applied to study a variety of neurological and psychiatric diseases, such as epilepsy [20], social anxiety disorder [21], major depression [22], Parkinson's Disease [23], hepatic encephalopathy [24], and Alzheimer's disease [25]. To the best of our knowledge, there has been no report on the neural mechanism of cognitive function impairments in ESRD patients using rs-fMRI with ReHo algorithm.…”

Abnormal spontaneous brain activity in minimal hepatic encephalopathy: resting-state fMRI study

“…This finding indicates decreased neuronal activity in those regions led by reduced cerebral oxygen consumption and cerebral blood flow (31). Previous MHE studies showed decreased regional homogeneity in the cuneus and precuneus (11,12) and weakened functional connectivity among the default mode network (14,15) suggesting an abnormal connection among these regions. As members of the default mode network, the precuneus and MPFC are responsible for cognition.…”

Regional homogeneity (ReHo) changes in new onset versus chronic benign epilepsy of childhood with centrotemporal spikes (BECTS): A resting state fMRI study

“…Nonetheless, questions to address in a longitudinal study are clearly raised here. Resample voxel size was set as 3 mm × 3 mm × 3 mm, which is a very common resampling voxel size for ReHo analysis (Chen et al, 2015; Ni et al, 2012; Ping et al, 2013). In this study, its original voxel size was 3.75 mm × 3.75 mm × 4 mm.…”