An empirical mathematical model applied to quantitative evaluation of thioacetamide-induced acute liver injury in rats by use of dynamic contrast-enhanced computed tomography.

Our purpose in this study was to apply an empirical mathematical model (EMM) to the quantitative evaluation of thioacetamide (TAA)-induced acute liver injury in rats by use of dynamic contrast-enhanced computed tomography (DCE-CT), and to investigate its usefulness in comparison with a dual-input, single-compartment model. The rats in the TAA-treated group were injected intravenously with 140 mg/kg body weight (n = 10) or 280 mg/kg body weight (n = 10) of TAA, whereas those in the control group (n = 10) were injected with saline instead of TAA. The DCE-CT studies were performed 2 days after injection of TAA or saline by use of a 4-detector row CT. The upper limit of the time-density curve (A), the rates of contrast uptake (α) and washout (β), the parameter related to the slope of early uptake (q), the area under the curve (AUC), the time to the maximum enhancement (T (max)), the maximum enhancement (C (Lmax)), and the elimination half-life of the contrast agent (T (1/2)) were calculated by use of the EMM. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were also measured. Both α and q decreased significantly in the rats of the TAA-treated group compared to those in the control group, whereas T (max) and T (1/2) increased significantly. The values of α, q, AUC, and T (max) were significantly correlated with both AST and ALT. Our results suggest that the EMM is useful for quantitative evaluation of TAA-induced acute liver injury and can be used as an alternative to the dual-input single-compartment model, especially when the vascular input functions cannot be obtained.