99mTc anti-D-dimer MoAb detects venous thrombi in man.

Authors' work is based on the ability of a 99mTc labelled antibody (MoAb) against D-Dimer (D-D) to visualize thrombi in man. D-Dimer is a specific epitope created during the cross-linking process of fibrin strains. Five normal volunteers and 5 patients with leg varices were given 10 mCi of 99mTc anti-D-Dimer MoAb (research approved by our Ethical Committee). Each patient gave his informed consent. Scintigraphic images were taken at 5, 60, 180 min. No adverse reaction was observed. Two patients underwent saphenous stripping 3 hrs after injection, in the other 4 patients scintigraphic images were acquired at 6 and 8 hrs. Twelve hot spots were visualized. Of these, 5 were localized during operation with a pencil-like probe and exsected. Specific activity of exsected thrombi, saphenal walls and blood samples was measured. Thrombus to vein wall ratio of 2.2 +/- 0.6 and a thrombus to blood of 3.1 +/- 0.8 was measured. In non operated patients the best scintigraphic images were obtained between 60 and 180 min. 99mTc anti-D-Dimer MoAb is a promising agent for localization of thrombi.