Double Pulsed Field Gradient Diffusion MRI of skeletal muscle is sensitive to muscle microstructure

Single pulsed field gradient (sPFG) diffusion MRI (dMRI) is a commonly researched tool to monitor changes in muscle microstructure associated with injury. Double pulsed field gradient (dPFG) dMRI has been used to characterize microstructure of neural tissues, but is not commonly applied to skeletal muscle. This study demonstrates both in silico and in vivo applications of dPFG dMRI to assess changes in muscle microstructure that are related to muscle function (e.g. fiber diameter). Additionally, a novel method for analyzing dPFG data called Diffusion Tensor Subspace Imaging (DiTSI) demonstrates high sensitivity to quantifiable biomarkers of muscle microstructure.