Vascular cryopreservation in microsurgery.

Cyropreservation of blood vessels has been carried out for some decades with variable results. A rabbit model was used to compare cryopreserved femoral artery allografts (n = 12 arteries), fresh autografts (n = 15 arteries), and fresh allografts (n = 16 arteries) at 1 and 3 months postoperatively. Patency rates were highest in the fresh autografts (86.7 percent), followed by the cryopreserved allografts (66.7 percent at 1 month and 83.3 percent at 3 months) and fresh allografts (62.5 percent at 1 month and 75 percent at 3 months). The fresh allografts showed the greatest alterations in endothelial cells and intima and muscle layer, followed by cryopreserved allografts, and then fresh autografts. Changes observed included pseudoendothelium formation, thickened intima, and thinner muscle layer. Cellular infiltrate appeared on the vessel walls only in the cryopreserved allografts (25 percent), but this did not have an effect on vascular patency. Fresh autografts remain the graft of choice for vascular defects, but cryopreserved allografts serve as the most appropriate option when the former are unavailable.