Histological validation of T1ρ mapping for liver fibrosis assessment in animal models of non-alcoholic fatty liver disease: a preclinical study

Motivation: Hepatic steatosis is a relevant confounder in T1 mapping, leading to the underestimation of hepatic fibrosis. T1ρ mapping may overcome this limitation. Goal(s): To validate T1ρ mapping for histologic grading of hepatic fibrosis in different animal models of non-alcoholic fatty liver disease (NAFLD). Approach: Three different NAFLD models were induced(n=57): (1)non-alcoholic fatty liver(NAFL), (2)non-alcoholic steatohepatitis(NASH), and (3)NASH-cirrhosis. Twelve rats were used as controls. Results: T1ρ values correlated significantly with histopathological markers of liver fibrosis and increased consistently with the severity of fibrosis. In contrast to native T1, hepatic steatosis did not influence T1ρ values. T1ρ values were associated with portal pressure measurements. Impact: NAFLD patients with NASH and advanced fibrosis are at increased risk of adverse outcomes. Early detection and follow-up are paramount. T1ρ has the potential to overcome the limitations of conventional mapping and become a reliable biomarker for liver fibrosis quantification.