Tract-Specific Analysis of Cervical Spinal Cord Aberrations in Multiple Sclerosis Patients at 3T

Motivation: Multiple sclerosis (MS) is a neuroinflammatory disease damaging the spinal cord (SC) necessitating advanced diffusion techniques to capture white matter (WM) tract pathology. Goal(s): We sought to combine tractography with scalar indices to characterize associations between individual SC WM fiber tract damage and MS disability metrics, an approach not extensively explored at 3T. Approach: We applied the iFOD2 tracking algorithm to the SC WM of patients with relapsing-remitting MS (pwRRMS) and healthy controls (HCs). Results: Streamline load was significantly associated with clinical indicators of worse disability. Decreased FA derived along streamlines was significantly associated with increased age, females, and worse mobility. Impact: We provide a novel method to visualize and characterize spinal cord pathology via tractography in multiple sclerosis patients that may be used to evaluate complex microstructural damage when combined with precise lesion location and scalar indices such as fractional anisotropy.