Investigation of quantitative magnetic resonance IVIM-DWI parameters in muscles of the lower limb at rest

This study investigates the use of quantitative magnetic resonance parameters—specifically Apparent Diffusion Coefficient (ADC) and Intravoxel-incoherent motion (IVIM) DWI metrics—to assess muscle perfusion and diffusion in the lower limbs of healthy volunteers versus patients with Peripheral Arterial Disease (PAD). The research aimed to evaluate the reproducibility of baseline (BL) and high-quality (HQ) MRI scans and also to determine whether these parameters could effectively differentiate between healthy and PAD-affected calf muscles. Results showed that ADC and the IVIM parameter ƒ exhibited moderate to excellent reproducibility and statistically significant differences between the two groups. In contrast, other IVIM parameters such as D* and D showed poor reproducibility and limited discriminatory power, likely due to background noise and sample size limitations. We conclude that ADC and ƒ are promising imaging biomarkers for characterizing restricted diffusion and impaired microvascular perfusion in PAD, with future research recommended to expand sample size and to explore the effects of exercise on the derived quantitative imaging biomarkers.