Duplex ultrasound in deep vein thrombosis

Colour duplex ultrasound may be used to produce a doppler image of blood flow within the veins and thus establish the presence of both occlusive and non-occlusive thrombosis or reflux.

The technique is good at detecting thrombosis in the iliac or femoral veins and indeed it is these and thromboses that extends above the knee that are more likely to embolise and require treatment. Its accuracy however in diagnosing below knee calf vein thrombosis remains unsatisfactory.

Ultrasound has the advantages of being simple and non-invasive. It has a high predictive value for thrombosis in veins above the knee, and this has been confirmed by venography.

Tailoring the length of anticoagulation treatment based on ultrasound

• trial evidence revealed that tailoring the duration of anticoagulation on the basis of ultrasonography findings reduced the rate of recurrent VTE in adults with proximal DVT (1)

Reference:

• 1) Prandoni P et al; AESOPUS Investigators. Residual thrombosis on ultrasonography to guide the duration of anticoagulation in patients with deep venous thrombosis: a randomized trial.Ann Intern Med. 2009 May 5;150(9):577-85.