Hepatocyte uptake ratio derived from T1 mapping for quantitative assessment of liver fibrosis

To investigate the diagnostic potential of T1 mapping-derived parameters for liver fibrosis, offering a quantitative approach to guide treatment strategies.

In this retrospective study, patients with chronic liver disease who underwent magnetic resonance imaging and pathological evaluation of the liver between April 2018 and May 2024 were included. The pre-contrast (T1pre) and post-contrast (T1post) T1 relaxation times, the difference between T1pre and T1post (ΔT1), reduction rates of T1 relaxation times, hepatocyte uptake ratio, and hepatocyte uptake index (KHep), were derived from pre-contrast and post-contrast T1 mapping images, and the liver-to-spleen signal intensity ratio (LSR) was measured on hepatobiliary phase images. One-way analysis of variance was used to compare differences in parameters across patients with mild (S0 + S1), moderate (S2 + S3) fibrosis, and cirrhosis (S4). Diagnostic performance was evaluated using the area under the receiver operating characteristic curve (AUC).

Eighty participants were enrolled, including 24 with mild fibrosis, 30 with moderate fibrosis, and 26 with cirrhosis. Serological scores (r = 0.361, 0.401), LSR (r = 0.410), and several conventional T1mapping-related parameters (r = 0.261-0.510) showed weaker correlations with liver fibrosis than hepatocyte uptake parameters (r = 0.549, 0.518). Only hepatocyte uptake ratio and KHep were always significantly different in patients with mild, moderate fibrosis, and cirrhosis (all p < 0.05). Among all parameters, the hepatocyte uptake ratio exhibited the highest AUC values for distinguishing moderate fibrosis (0.788, 95% CI: 0.682-0.893) and cirrhosis (0.795, 95% CI: 0.697-0.894).

The hepatocyte uptake ratio shows strong potential as a simple, non-invasive imaging biomarker for assessing liver fibrosis and guiding clinical management.

Question Hepatocyte uptake ratio calculated using a two-compartment model has good efficiency in assessing liver function, but has not been studied in liver fibrosis. Finding Hepatocyte uptake ratio has the best diagnostic efficiency for liver fibrosis and cirrhosis compared to serological scores, LSR, and conventional T1 mapping parameters. Critical relevance By applying a two-compartment model to exclude the extracellular space's influence on T1-shortening effect, the hepatocyte uptake ratio outperformed serological scores, LSR, and conventional T1 mapping parameters, offering a promising tool for the non-invasive diagnosis of liver fibrosis and cirrhosis.