Prothesis interposition revascularization in microvascular neurosurgery. Animal experience.

The rapid expansion of the field of microvascular neurosurgery has markedly increased the need for small arterial substitutes. For example sometimes the scalp arteries, the STA or the occipital artery, are unavailable to performe extra-intracranial by-pass, or someone need a high bypass flow immediately after the bypass operation. Generally vein and arterial grafts are used for this purpose. Synthetic Proteses, if proved satisfactory, would posses many advantage, including adequate supply in variery of size and shapes. At the present time the problem of a vascular prosthesis for a small caliber artery (less than 4 mm) is the patency and the thickness of wall. We studied a new small caliber vascular prosthesis model with "biolized" polymeric material obtained by mixing synthetic polyurethanes with the plasma protein fibrinogen of human origin. We implanted small prostheses with internal diameter less than 4 and 3 mm on rabbits and kids: the thickness of wall was about 0.1-0.2 mm; the inner surface had high porosity; the patency was controlled by microprobe of pulsed Doppler in acute stage (3 hours) and observed after one or two weeks of impiantation by angiographic exam. The graft was than removed and underwent an histological study.