Experimental Study of L-shaped Silastic Stents for Microvascular Anastomosis.

The stent technique of microvascular anastomosis, in which a stent is placed in the vessel before creating the anastomosis, is useful for accurate anastomosis formation, but the manipulation involved in stent insertion into the vessel and withdrawal from the anastomosis still poses problems. In this study, a silastic stent containing a copper wire-bent in an L-shape was designed and its utility in microvascular anastomosis was investigated in rats. Eighty end-to-end anastomosis procedures of the right femoral artery and vein were performed in rats. Anastomoses were conducted either by the conventional method (Method C) or using L-shaped silastic stents (Method L), with anastomosis condition assessed after one side had been sutured, at the completion of vascular anastomosis and on postoperative day 7. After one side had been sutured, suture errors were observed in three veins with Method C. At the completion of vascular anastomosis, impaired blood flow was observed in two arteries and two veins with Method C, and in one artery with Method L. On postoperative day 7, impaired blood flow was observed in one artery and one vein with Method C and in one vein with Method L. The use of L-shaped silastic stents preserved the advantages of the stent technique while simplifying stent manipulation. This technique may help reduce the risk of intimal trauma.