Dynamic radionuclide phlebography. A clinical study in patients after total hip replacement.

Dynamic radionuclide phlebography was performed in 50 consecutive patients after total hip replacement to evaluate the diagnostic value of the method compared to contrast phlebography. The investigation was limited to the diagnosis of iliofemoral thrombi. A special injection technique was developed and flow curves, mean transit time and distribution of flow were recorded with a scintillation camera interfaced to a digital computer. Three principally different types of flow curves were observed. Mean transit time was of value in differentiating particle flow in the superficial veins from passage through the deep veins. Out of 15 legs with thrombi in the iliofemoral region, the distribution of flow was significantly changed in 12. Deep vein thrombosis in the lower leg did not influence mean transit time or distribution of flow in the iliofemora region. Extensive collateral flow was rare. Ninety per cent of the thrombi were asymptomatic. The method compares favorably with the 125 I fibrinogen method and cuff impedance phlebography, in diagnosing iliofemoral thrombi after total hip replacement.