Controversies in the use of lower extremity sonography in the diagnosis of acute deep vein thrombosis and a proposal for a unified approach.

During the past 10 years, lower extremity venous ultrasonography (LEUS) has essentially replaced contrast venography for the evaluation of patients suspected of acute thromboembolic disease. Along with this change in technology, the number of studies performed to rule out DVT has increased dramatically, and there has been controversy in the literature regarding the most appropriate role of LEUS. Specifically, four questions have been raised: (1) What is the appropriate role of LEUS in patients with a nondiagnostic V/Q scan?; (2) Is there a need to examine the contralateral (asymptomatic) leg of patients presenting with unilateral DVT symptomatology?; (3) What role, if any, does LEUS play in the evaluation of patients with bilateral leg symptoms?; and (4) When can a limited examination of the leg be performed? The purpose of this article is to provide a balanced review of these issues and to present an algorithm for a reasonable, integrated approach to the use of LEUS among patients suspected of having acute thromboembolic disease.