Deep Vein Thrombosis and Its Diagnosis

Deep vein thrombosis of the legs is a common occurrence in hospitalized patients, and this is especially true after major orthopaedic surgical procedures. There is a strong association between deep vein thrombosis and pulmonary embolism, particularly if thrombosis involves the proximal deep veins. The mortality from pulmonary embolism can be significantly reduced by timely diagnosis and treatment. Postthrombotic syndrome is a frequent result of deep vein thrombosis and is a leading cause of chronic venous disease, being implicated in the majority of cases of venous ulceration. There may be an estimated 24 million patients in the United States with chronic venous insufficiency, 7 million patients with trophic cutaneous changes, and a half million patients with skin ulceration. Modern methods of recanalization of thrombosed deep veins, applied early in the process, can limit the frequency and severity of postthrombotic syndrome. Diagnosis of venous thrombosis can be made by noninvasive means as well as contrast venography. Venography has traditionally been the "gold standard," but its use has declined because of the ease of use as well as the accuracy of ultrasound. However, there remains a need for venography in specific circumstances, and knowledge of proper technique, limitations, and interpretive criteria is essential for optimizing its use.