Deep venous thrombosis: recent advances and optimal investigation with US.

Compression US is the imaging procedure of choice for patients with clinically suspected DVT of the lower and upper extremities. Clinical trials have validated the safety of the approach of relying on two negative US studies obtained 1 week apart to safely exclude the diagnosis of DVT. In selected low-risk patients, the diagnosis of DVT may be excluded by a single negative US study. US has a role to play in the management of patients with suspected pulmonary embolism who have nondiagnostic pulmonary imaging studies.