DUPLICATED SUPERFICIAL FEMORAL VEINS - A SOURCE OF ERROR IN THE SONOGRAPHIC INVESTIGATION OF DEEP-VEIN THROMBOSIS

PURPOSE: To determine whether the number of false-negative ultrasound (US) findings of thrombosis is larger when a duplicated femoropoplitea l venous system is present. MATERIALS AND METHODS: A retrospective rev iew was performed of 381 venograms obtained after initial US findings were considered negative for thigh or popliteal thrombosis in patients in whom deep vein thrombosis was suspected. Venograms were evaluated for the presence of thrombosis and the presence and configuration of d uplicated superficial femoral veins. RESULTS: Multiple superficial fem oral veins were present on 177 (46%) of the 381 venograms; 149 (84%) w ere duplex systems,false-negative US findings occurred in four (2%) of 204 patients with single femoral veins and in 10 (6%) of 177 patients with duplicated femoral veins (P = .056, not statistically significan t). CONCLUSION: The frequency of missed proximal thrombosis at sonogra phy appears to be increased when duplicated superficial femoral veins are present. Data from clinical and imaging studies are insufficient t o support the adoption of a totally noninvasive imaging strategy.