Mapping spinal cord vascular reactivity and vascular territories using fMRI in highly sampled individuals

Motivation: Impaired vascular function in the spinal cord contributes to numerous neurological pathologies and it is important to be able to image those changes in individuals. Goal(s): Map spinal cord vascular reactivity (SCVR) amplitude and hemodynamic delay at the individual level in two highly sampled adults. Approach: Participants performed 18 spinal cord fMRI runs of a breath-holding task. SCVR amplitude was mapped using an end-tidal CO2 regressor and hemodynamic delay was mapped by temporally shifting that regressor. Results: Individual SCVR amplitude and hemodynamic delay maps reveal an earlier ventral response and later dorsal response, aligning with vascular territories of the cervical spinal cord. Impact: Individual maps of spinal cord vascular reactivity (SCVR) hemodynamic delay align with arterial territories. These are the first non-invasive maps of vascular territories in the human spinal cord. Future work will map altered SCVR in patients with neurological conditions.