ABSTRACT
Microsurgical free tissue transfer is currently associated with very high success rates and few complications. While interposition vein grafting is clearly an important adjunct to the microsurgeon's armamentarium, it has been associated with higher free flap/replantation failures and complication rates. With appropriate flap planning and surgical techniques, the need for interposition vein grafting should be quite infrequent and hopefully avoided if at all possible. Nevertheless, when necessary, the vein graft remains the gold standard, with virtually all alternative interposition grafts demonstrating lower patency rates. One of the more promising areas of research is the concept of genetic manipulation of the endothelial cell via molecular biological techniques. It is likely that in the near future this may become a clinical reality, not only improving the patency of microsurgical anastomoses and interposition vein grafts, but quite possibly altering the target organ functionally as well.