Diffusion MRI Reveals Distinct Abnormalities in the Spinal Cord Following Unilateral Dorsal Column Lesion and Sensory Nerve Root Injury

Motivation: Neurite orientation dispersion and density imaging (NODDI) and diffusion tensor imaging (DTI) offers specific metrics for assessing post-injury structural changes in the spinal cord. Goal(s): This study aims to detect regional alterations in the spinal cord of non-human primates after unilateral dorsal column lesion (DCL) and dorsal sensory root lesion (DSRL) at the cervical level. Approach: Both NODDI and DTI measures were quantified and compared for assessing changes in different injury models. Results: Findings show secondary injury in both models, with DCL affecting more regions than DSRL. NODDI metrics confirm cyst formation and detect subtle changes in the dorsal root entry zone. Impact: Neurite orientation dispersion and density imaging (NODDI) offers specific and sensitive metrics to assess early spinal cord structural changes post-injury. NODDI detects cysts after dorsal column lesion and subtle alterations in the dorsal root entry zone after sensory root injury.