Digital angiography of the feet of horses

To describe the vascular anatomy of the palmar digital artery and its major branches in the equine foot and to quantify the diameter of these vessels by use of digital angiograms. Sample Population-6 thoracic limbs obtained from 6 horses.

Distal portions of each limb were perfused with aerated Krebs-Henseleit solution. Digital angiograms were acquired in standing and lateral recumbent positions, following an intra-arterial injection of iopamidol. Select vessels were measured on radiographic views, and values were corrected for magnification.

The palmar digital artery tapered from 2.28 mm at the coronary region to 1.61 mm at the entrance to the solar canal, and the major arterial branches ranged in diameter from 0.71 to 1.42 mm in the standing position.

Digital angiography is useful for imaging small vessels, but penumbra limits the image resolution of the macrovasculature of the foot. The palmarodorsal projection is more useful for evaluation of the terminal arch and solar branches, but 2 projections are necessary for a thorough examination of the foot. Image magnification, position of horse, and vascular response to contrast medium must be considered in the quantitative assessment of vessel diameter. Digital angiography may be performed in clinical cases and research models for examination of vascular perfusion of the distal portion of the limb.