Numerical Validation of Multi-Compartment Diffusion Biomarkers of Peripheral Nerve Trauma

Motivation: The spherical mean technique (SMT) is a multi-compartmental diffusion model that has been used to evaluate axonal loss in the brain. This method holds promise as a biomarker of peripheral nerve regeneration following injury and surgical repair but has yet to be validated. Goal(s): This study aims to validate the use of the multi-compartmental diffusion MRI in peripheral nerve imaging. Approach: The SMT technique was validated via computational modeling studies based on light microscopy data of rats' sciatic nerves. Results: We found that the SMT specifically assays axonal regeneration after trauma, even in the presence of other potentially confounding features. Impact: The spherical mean technique (SMT), a multi-compartmental diffusion MRI model, demonstrated potential as a biomarker of peripheral nerve regeneration following injury and surgical repair.