Obstructive peripheral vascular disease is widespread in modern society. Approximately 62,000 non-coronary vascular stenting procedures are conducted annually in the U. S. to treat the disease. Even with the implantation of a stent, the restenosis ratio is high--up to fifty percent-- which means that there is a significant need for treatment. The only method that has been shown to reduce or completely inhibit restenosis is the application of ionizing radiation. Iridium-192-tipped catheters have been used for this application, but the radiation safety problems associated with the technique call for a different approach to the problem. Implant Sciences proposes to do so by placing a low dose rate of gamma radiation on the stent itself. Irradiation has heretofore never been applied to peripheral stents. Using an existing ion implanter to deliver ytterbium-169, a gamma emitter, to the stents, animal testing is proposed to evaluate the restenosis-inhibiting qualities of these devices. If they prove as effective as iridium-192, their much lower radioactivity should result in their acceptance as the preferred method of suppressing restenosis. PROPOSED COMMERCIAL APPLICATIONS: This research will lead to a process for ion implantation of radioisotopes into peripheral stents. ISC has had interest from several stent manufacturers who plan to offer radioactive stents as soon as FDA approval is received. ISC plans to ion implant radioisotopes in their stents as a manufacturing service.