Reliability of Doppler ultrasound in the diagnosis of acute venous thrombosis both above and below the knee.

We have found the Doppler examination to be accurate in 92% of limbs with suspected iliofemoral thrombosis and in 86% of limbs with suspected calf vein thrombosis. Above the knee, the sensitivity was 94% and the specificity, 90%. Below the knee, the sensitivity was 91% and the specificity, 84%. In the hands of a skilled examiner, Doppler ultrasound is a reliable noninvasive technique for evaluating patients with suspected deep venous thrombosis and one on which therapy can safely be based.