Evaluation of microvascular permeability of skeletal muscle and texture analysis based on DCE-MRI in alloxan-induced diabetic rabbits

Objectives To estimate the microvascular permeability and perfusion of skeletal muscle by using quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and explore the feasibility of using texture analysis (TA) to evaluate subtle structural changes of diabetic muscles. Methods Twenty-four rabbits were randomly divided into diabetic ( n = 14) and control ( n = 10) groups, and underwent axial DCE-MRI of the multifidus muscle (0, 4, 8, 12, and 16 weeks after alloxan injection). The pharmacokinetic model was used to calculate the permeability parameters; texture parameters were extracted from volume transfer constant ( K trans ) map. The two-sample t test/Mann-Whitney U test, repeated measures analysis of variance/Friedman test, and Pearson correlations were used for data analysis. Results In the diabetic group, K trans and rate constant ( K ep ) increased significantly at week 8 and then showed a decreasing trend. Extravascular extracellular space volume fraction ( V e ) increased and plasma volume fraction ( V p ) decreased significantly from the 8th week. Skewness began to decrease at the 4th week. Median K trans and entropy increased significantly, while inverse difference moment decreased from the 8th week. Energy decreased while contrast increased only at week 8. Muscle fibre cross-sectional area was negatively correlated with V e . The capillary-to-fibre ratio was positively correlated with V p ( p < 0.05, all). Conclusions Quantitative DCE-MRI can be used to evaluate microvascular permeability and perfusion in diabetic skeletal muscle at an early stage; TA based on K trans map can identify microarchitectural modifications in diabetic muscles. Key Points • Four quantitative parameters of DCE-MRI can be used to evaluate microvascular permeability and perfusion of skeletal muscle in diabetic models at early stages. • Texture analysis based on K trans map can identify subtle structural changes in diabetic muscles.