Assessment of deep venous thrombosis

: Deep vein thrombosis (DVT) is a frequent disorder, which should not be missed diagnostically because of the associated morbidity and mortality due to pulmonary embolism and the postthrombotic syndrome. Clinical diagnosis is unreliable. Because of the possible risks a treatment by anticoagulation should not be undertaken without objective confirmation of DVT. Venography is generally considered as the gold standard for the diagnosis of DVT, but is invasive and associated with side effects. Noninvasive cw-Doppler ultrasound and the plethysmography are simple methods, but the accuracy is sufficient only for symptomatic proximal DVT and not for isolated DVT of the calf. In the past few years (color-coded) venous duplex imaging gained increasing importance. It is a noninvasive test with an accuracy comparable to that of venography. In addition to vascular changes perivascular structures can be investigated. B-mode compression sonography has a comparable accuracy for symptomatic proximal DVT.