Hybrid Diffusion Imaging in a Spinal Cord Model of Dysmyelination

Introduction: Diffusion tensor imaging (DTI) is widely used for the study of white matter (WM) diseases and fractional anisotropy (FA) is commonly used as a measure of WM integrity. However, FA is also highly sensitive to such factors as non-Gaussian diffusion, crossing fibers and imaging noise, which may impair its specificity. Other DT measures, such as axial diffusivity (Da) and radial diffusivity (Dr), are similarly limited. It has been suggested that the former is related to axonal integrity while the latter is related to myelination [1]. In addition to DTI, q-space imaging and diffusion spectrum imaging (DSI) have also been utilized to extract additional information about WM microstructure [2, 3].