RADIOCHEMISTRY AIMD RADIOPHARMACEUTICALS lndium-111-Labeled Autologous Platelets for Location of Vascular Thrombi in Humans

Twenty-two patients suspected of having either venous or arterial thrombi were studied with In-Ill-labeled autologous platelets. Whole-body scans were performed 3, 24, and 48 hr following i.v. injection. Twelve patients studied with saline-washed platelets had unsatisfactory 15-min recovery and biologic half-time. When the labeling was carried out in plasma, these values compared favorably with normal values reported for Cr-51-labeled autologous platelets. Of ten patients studied using platelets labeled in plasma, three had normal scans, six had abnormal scans, and one had an equivocal scan. All six abnormal scans were confirmed with corresponding positive findings in either the venogram, arteriogram, or lung scan.