The development of synthetic vascular Prostheses has greatly extended the indications for and employment of procedures for replacement or bypass of occluded arterial segments. Problems which limit the usefulness of homografts, namely, availability and difficulties of sterilization and preservation, are obviated by the use of synthetic grafts to the extent that the artificial materials have almost supplanted the naturally occurring homograft as blood vessel substitutes.
As experience with synthetic grafts accumulates, it becomes apparent that they possess certain distinctive properties. Among these is their ability to function as vascular channels when uncovered by surrounding soft tissues and/or in the presence of infection. This quality, not possessed by homografts, would appear to be fortunate indeed, and so it is. Yet it is not an unmixed blessing! For while an exposed or infected synthetic prosthesis continues to function as a blood conduit, it also functions as a foreign body, vigorously resisting attempts