Quantification of vascular perfusion in the spinal cord after injury.

Abstract

Traumatic injury destroys blood vessels at the injury epicenter and is followed by local angiogenesis and regional inflammation. Healing from injury depends on vascular health because blood supply is directly responsible for the health and function of surrounding tissue. This work establishes a new method for qualitatively and quantitatively measuring the blood supply of spinal cord (SC) tissue. Systemically injecting fluorescent microspheres (FMs) and cryostat sectioning SC tissue reveals a novel and potentially powerful way of assessing blood supply. This method is easily incorporated with existing tissue processing protocols because it does not require chemical digestion of the tissue region of interest. FM blood supply measurements show that after mild contusion injury, the epicenter has less blood flow while the blood flow several millimeters rostral and caudal to the epicenter is elevated compared to uninjured controls. The time course for vascular repair after spinal cord injury (SCI) has been widely studied and this pilot experiment was carried out seven days post-injury, at which point angiogenesis has reached its zenith and vascular pruning is minimal. A custom MATLAB program is used to automatically analyze FM distribution