Objectives: We evaluated the interpretation, reliability and usefulness of 99m technetium labelled antifibrin immunoscintigraphy for the diagnosis of deep vein thrombosis in the lower limbs.
Methods: The diagnostic value of 99m technetium labelled antifibrin immunoscintigraphy was assessed in 44 patients with suspected venous thrombosis. The reference examination was bilateral ascending phlebography; 40 patients had doppler ultrasonography of the veins; 0.5 mg of antibody labelled by 17.5 mCi on average of 99m technetium were injected intravenously, and serial scintigraphic images were collected 1 min, 90 min and 18 hours after injection.
Results: The best results were obtained by comparison between the 90 min and the immediate post-injection images, with 86 percent sensitivity, 73 percent specificity and 81 percent accuracy. Heparin therapy and past history of phlebitis had no influence on the results. The doppler ultrasonography/immunoscintigraphy combination had a 100 percent specificity. 99m Technetium labelled antifibrin immunoscintigraphy had about the same diagnostic value as 111 indium labelled antifibrin immunoscintigraphy.
Conclusion: The introduction of 99m technetium as isotopic marker will make immunoscintigraphy easier and available in numerous nuclear medicine centres. Antifibrin immunoscintigraphy can be an additional diagnostic tool for the difficult diagnosis of deep vein thrombosis.