The significance of increased 111indium platelet accumulation at post-angioplasty sites.
We assessed prospectively the significance of 111indium labelled platelet accumulation following angioplasty procedures in 12 patients (9 femoral angioplasties (2 laser, 1 atherectomy) and 3 iliac stents). Autologous 111indium labelled platelets were re-injected immediately after angioplasty. Radioactivity was measured over treated and reference sites, by single probe and gamma camera, and expressed as a radioactivity ratio (RR). All patients had duplex ultrasound assessment and occlusions were confirmed by arteriography. RR was always raised after angioplasty. Three patients who had acute occlusions showed markedly raised average RRs (significant at 99% ANOVA). RR was not raised after laser assisted angioplasty, however, our numbers were small. 111Indium platelet radioactivity did not predict subsequent occlusion after angioplasty but effectively detected existing acute post-angioplasty occlusions.