抄録
The porosity of vascular prosthesis is concerned with blood leak, the formation of initial fibrin matrix layer and their ultimate organization. In initial stages after implantation a high porous, fine-texture surface structure of the prosthesis has a effect of producing a thin, uniform coat of coagula. Blood leak tends to be less with those prostheses in which interstices between staple fiber are narrow and winding, even high porous. The pseudointima which has been formed to be thinly and smoothly is held in place by an anchoring effect and obtains sufficient nutrients directly from circulating blood, even if impermeable and thus shows favorable processes of organization. When large amounts of coagula filled up the pore of prosthesis in step of preclotting this is followed by a release of coagulative substances from the coagula secondarily, which in turn gives rise to an increase in thrombus formation with a resultant occlusion of the prosthesis. Moreover, it is also likely that the coagula is eventually replaced with collagen fibers which leads to increased rigidity of the prosthesis.
From the above it seems inappropriate to idea that vascular prostheses of large permeability are excellent. Now the suggestion that the porosity of vascular prosthesis to increase to a maximum allowable for the prevention of blood leak should be reconsidered.
