Duplex B-mode imaging for the diagnosis of deep venous thrombosis.

Real-time B-mode venous imaging has numerous advantages for the diagnosis of acute deep venous thrombosis (DVT). During the 11 months ending Feb 1, 1986, we examined 431 patients for possible acute DVT using a 5-MHz hand-held continuous wave Doppler stethoscope and a duplex real-time B-mode imager. Clots were seen in 86 patients in multiple views and cross sections. Normal veins completely collapsed with probe pressure on the skin. Blood flow was seen and heard, and abnormal flow was detected. There were no false-negatives (100% sensitivity). Early in the study, two false-positives occurred (78% specificity), but these errors will not recur. These tests are accurate, noninvasive, and inexpensive. They differentiate acute from chronic thrombosis and are repeatable. Duplex imaging may become the "gold standard" for the diagnosis of DVT.