title: Identifying minimal hepatic encephalopathy in cirrhotic patients by measuring spontaneous brain activity.
abstract: It has been demonstrated that minimal hepatic encephalopathy (MHE) is associated with aberrant regional intrinsic brain activity in cirrhotic patients. However, few studies have investigated whether altered intrinsic brain activity can be used as a biomarker of MHE among cirrhotic patients. In this study, 36 cirrhotic patients (with MHE, n = 16; without MHE [NHE], n = 20) underwent resting-state functional magnetic resonance imaging (fMRI). Spontaneous brain activity was measured by examining the amplitude of low-frequency fluctuations (ALFF) in the fMRI signal. MHE was diagnosed based on the Psychometric Hepatic Encephalopathy Score (PHES). A two-sample t-test was used to determine the regions of interest (ROIs) in which ALFF differed significantly between the two groups; then, ALFF values within ROIs were selected as classification features. A linear discriminative analysis was used to differentiate MHE patients from NHE patients. The leave-one-out cross-validation method was used to estimate the performance of the classifier. The classification analysis was 80.6 % accurate (81.3 % sensitivity and 80.0 % specificity) in terms of distinguishing between the two groups. Six ROIs were identified as the most discriminative features, including the bilateral medial frontal cortex/anterior cingulate cortex, posterior cingulate cortex/precuneus, left precentral and postcentral gyrus, right lingual gyrus, middle frontal gyrus, and inferior/superior parietal lobule. The ALFF values within ROIs were correlated with PHES in cirrhotic patients. Our findings suggest that altered regional brain spontaneous activity is a useful biomarker for MHE detection among cirrhotic patients.
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China. chj0075@126.com.
authors.forename: Hua-Jun
authors.initials: HJ
authors.lastname: Chen
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Infectious Diseases, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China.
authors.forename: Long-Feng
authors.initials: LF
authors.lastname: Jiang
authors.affiliation: School of Information Science and Engineering, Central South University, Changsha, 410083, China.
authors.forename: Qiu-Feng
authors.initials: QF
authors.lastname: Chen
authors.affiliation: Department of Infectious Diseases, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China. dr-lijun@vip.sina.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China. shihb@vip.sina.com.
authors.forename: Hai-Bin
authors.initials: HB
authors.lastname: Shi
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D059907:Functional Neuroimaging; D006501:Hepatic Encephalopathy / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
keywords: Amplitude of low-frequency fluctuations; Cirrhosis; Functional magnetic resonance imaging; Minimal hepatic encephalopathy