Evaluation of Hepatic Tissue Blood Flow Using Xenon Computed Tomography with Fibrosis Progression in Nonalcoholic Fatty Liver Disease: Comparison with Chronic Hepatitis C

Abstract

AimsThe present study evaluated the utility of xenon computed tomography (Xe-CT) as a noninvasive diagnostic procedure for the measurement of hepatic tissue blood flow (TBF) in patients with nonalcoholic fatty liver disease (NAFLD) or chronic hepatitis C (CH-C).MethodsXe-CT was performed in 93 patients with NAFLD and in 109 patients with CH-C. Subjects were classified into one of three groups, based on fibrosis stage: group 1, no bridging fibrosis; group 2, bridging fibrosis; and group 3, liver cirrhosis. Correlations between hepatic TBFs in each fibrosis stage were examined.ResultsIn group 1, portal venous TBF (PVTBF), hepatic arterial (HATBF), and total hepatic TBF (THTBF) were significantly lower in patients with in nonalcoholic steatohepatitis (NASH) than in those with CH-C (p < 0.001, p < 0.05, p < 0.001, respectively). In group 2, PVTBF and THTBF were significantly lower in patients with in NASH than in those with CH-C (p < 0.001, p < 0.05, respectively). In group 3, hepatic TBFs were not significantly different when comparing patients with NASH and those with CH-C.ConclusionsPVTBF decreased due to fat infiltration. Therefore, hemodynamic changes occur relatively earlier in NAFLD than in CH-C. Patients with NASH should be monitored carefully for portal hypertensive complications in the early fibrosis stage.

Assessment of Nonalcoholic Fatty Liver Disease in Rats Using Quantitative Dynamic Contrast‐Enhanced MRI

“…Since perfusion fraction represents the fraction of diffusion linked to microcirculation (blood volume), the decrease of perfusion fraction indicates a decreased perfusion in livers with NAFLD. Portal vein tissue blood flow (PVTBF) obtained from Xe‐CT was found to be lower in advanced NASH than in early NASH, as well as lower in early NASH than in simple steatosis, while hepatic arterial tissue blood flow (HATBF) did not significantly increase . Previously, DCE‐MRI parameters have been frequently used as predictive biomarkers for angiogenic activity in tumors.…”

“…It is reasonable that HABR might be present in NAFLD as well. Recent studies using Xe‐CT showed that NAFLD resulted in the reduction of whole liver tissue blood including total arterial tissue blood flow (THTBF), PVTBF, and HATBF, but PVTBF was affected more obviously . This might lead to a relatively increased ratio of HATPF to THTBF, which causes the increase of HPoI.…”

“…Portal vein tissue blood flow (PVTBF) obtained from Xe-CT was found to be lower in advanced NASH than in early NASH, as well as lower in early NASH than in simple steatosis, while hepatic arterial tissue blood flow (HATBF) did not significantly increase. 12,27 Previously, DCE-MRI parameters have been frequently used as predictive biomarkers for angiogenic activity in tumors. These parameters are found to be associated with the tumor grade, microvessel density, and vascular endothelial growth factor (VEGF) expression.…”

“…Diffusion‐weighted (DW) MRI on the basis of the intravoxel incoherent motion (IVIM) theory in patients with type 2 diabetes has revealed that steatosis can affect diffusion parameters and perfusion fraction . Xenon computed tomography (Xe‐CT) has been used to measure hepatic tissue blood flow for differential diagnosis between the NAFLD and cirrhosis . However, approaches with the capacity for early diagnosis and dynamic monitoring of NAFLD remains limited.…”

“…11 Xenon computed tomography (Xe-CT) has been used to measure hepatic tissue blood flow for differential diagnosis between the NAFLD and cirrhosis. 12 However, approaches with the capacity for early diagnosis and dynamic monitoring of NAFLD remains limited. Previously, proton density fat fraction (PDFF) measurement by MRI showed promise for assessment of hepatic steatosis grade in patients with NAFLD.…”