Measurement of equine laminar blood flow and vascular permeability by use of dynamic contrast-enhanced computed tomography.

The research examined how dynamic contrast-enhanced computed tomography (CT) was used to measure blood flow, vascular permeability, and fractional vascular volume in the laminar regions of healthy horses.

Methods

• The subjects of the study were nine adult horses, all of which were not lame and exhibited no abnormalities in their laminae or phalanges as determined by radiographic examination.
• Each horse was anesthetized and placed on either their right or left side, with the dependent forelimb in the CT gantry. Only one limb per horse was scanned.
• They used an iodinated contrast medium, which was infused while serial 10-mm collimated transverse CT images were taken at the same location every other second for 90 seconds.
• The resulting images were then processed using custom software designed to estimate the blood flow, vascular permeability, and fractional vascular volume in the horses’ dorsal, dorsomedial, and dorsolateral laminar regions.

Results

• Among the forelimbs of the nine horses, the average blood flow in the dorsal laminar region was 0.43 +/- 0.21 mL*min(1)*mL(1), while the average blood flows in the dorsomedial and dorsolateral laminar regions were 0.26 +/- 0.16 mL*min(1)*mL(1) and 0.24 +/- 0.16 mL*min(1)*mL(1), respectively.
• The mean vascular permeability in the dorsal, dorsomedial, and dorsolateral laminar regions was 0.09 +/- 0.03 mL*min(1)*mL(1), 0.16 +/- 0.06 mL*min(1)*mL(1), and 0.12 +/- 0.06 mL*min(1)*mL(1), respectively.
• The average fractional vascular volume in these regions was 0.63 +/- 0.20, 0.37 +/- 0.14, and 0.34 +/- 0.17, respectively.

Conclusion

• The findings indicate that dynamic contrast-enhanced CT can be used to non-invasively measure blood flow, vascular permeability, and fractional vascular volume in horses’ laminar regions.