131I-labeled fibrinogen in the diagnosis of deep vein thrombosis of the lower extremities.

Autologous 131I-labeled fibrinogen was administered to 17 patients during 19 episodes of suspected lower extremity deep vein thrombosis in an attempt to assess its diagnostic accuracy. Serial rectilinear scanning and probe counting of the lower extremities and pelvis were performed and compared with ascending contrast venography. The sensitivities of imaging and counting were 67% and 47%, respectively, and both had a specificity of 95%. The experience with evaluation of deep vein thrombosis of the pelvic and iliac veins was small but suggested that 131I fibrinogen will be of limited use in those vessels.