Blood-spinal cord barrier permeability in experimental spinal cord injury: dynamic contrast-enhanced MRI

Following the primary traumatic injury, spinal cord tissue undergoes a series of pathobiological changes, including compromised blood-spinal cord-barrier (BSCB) integrity. These vascular changes occur over both time and space. In an experimental model of spinal cord injury (SCI), longitudinal dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)studies were performed up to 56 days post-SCI to quantify spatial and temporal changes in the BSCB permeability in tissue that did not show any visible enhancement on the post-contrast MRI(non-enhancing tissue). DCE-MRI data was analyzed using a two-compartment pharmacokinetic model. These studies demonstrate gradual restoration of BSCB with post-SCI time. But, based on DCE-MRI, and confirmed by immunohistochemistry, the BSCB remained compromised even at 56 days post-SCI. In addition, open-field locomotion was evaluated using the 21 point Basso-Beattie-Bresnahan scale. A significant correlation between decreased BSCB permeability and improved locomotor recovery was observed.