INVIVO EVALUATION OF ANTITHROMBOGENICITY FOR ION-IMPLANTED SILICONE-RUBBER USING INDIUM-111-TROPOLONE PLATELETS

H-2+, N2+, O2+, and Ne+ ion implantations into silicone rods were performed at 150 keV with doses ranging from 1 x 10(17) to 3 x 10(17) ions/cm2 to improve antithrombogenicity. The antithrombogenicity was tested by the superior vena cava (SVC) indwelling method for two days in rats with In-111-tropolone platelets, and by the inferior vena cava (IVC) indwelling method for periods of one to seven weeks in dogs. Results of the SVC indwelling method showed that platelet accumulation on H-2+ and O2+ implanted specimens decreased. In particular 1 x 10(17) O2+/cm2 implantation caused both accumulation onto specimens and a decrease of the SVC. Macroscopic views of the ion implanted IVC specimens in dogs revealed little thrombus formation. It is concluded that ion implantation into silicone rod is a useful technique to improve its antithrombogenicity.