Methodology for MR diffusion tensor imaging of the cat spinal cord

Magnetic resonance diffusion tensor imaging (DTI) of the spinal cord is challenging because of the cord's thin structure and the presence of physiological and susceptibility artifacts. To circumvent these issues, we developed a methodology for imaging the thoraco-lumbar spinal cord of cats at 3 T using single-shot spin-echo echo planar imaging (ss-SE-EPI). The proposed method could potentially be applied to humans since it was developed on a clinical scanner with a standard spine coil. Results provide (i) suggestions for optimal slice orientation and phase encoding direction; (ii) an assessment of the benefits of parallel imaging to reduce geometric distortions; (iii) feasibility of acquiring quality diffusion weighted data in 13 minutes at a resolution of 1.1 mm and (iv) determination of axonal disruption, in two cats with complete spinal cord transection, using tractography.