This study aimed to determine the relationships between magnetic resonance elastography (MRE) imaging biomarkers and the stages of liver fibrosis in a rabbit model of liver fibrosis, a longitudinal validation for clinical translation. Liver fibrosis was induced in 38 male New Zealand rabbits by weekly subcutaneous injections of 0.1 ml 50% carbon tetrachloride oily solution per kilogram of body weight for 4 to 10 weeks to produced varying degrees of liver fibrosis. The values for the liver stiffness (LS) MRE imaging biomarkers were measured at different stages of liver fibrosis. Masson trichrome staining of liver tissue was used to identify collagen tissue. Among the 38 rabbits, the histological studies showed liver fibrosis stage 1 (F1, n = 11), liver fibrosis stage 2 (F2, n = 8), liver fibrosis stage 3 (F3, n = 7), and liver fibrosis stage 4 (F4, liver cirrhosis, n = 12). Additional healthy rabbits served as controls (F0, n = 15). During liver fibrosis progression, the mean LS values increased during liver fibrosis progression. There were significant differences in LS values between (F0 and F1) and (F2 and F3), (F2 and F3) and (F4), and (F0 and F1) and (F4), which are three clinically relevant fibrosis groups. There was a high correlation between the LS values measured by MRE and the stages of liver fibrosis determined by histology (R2 = 0.67, P < 0.001). MRE imaging has the potential to serve as a noninvasive, unenhanced imaging technique for liver fibrosis diagnosis and staging.
Keywords: Liver fibrosis; diagnosis; imaging biomarker; magnetic resonance elastography.