Duplex sonography of lower extremity arteries.

Although indirect noninvasive tests continue to play a role in the evaluation of patients with lower extremity arterial disease, the direct approach of duplex scanning provides both anatomic and physiological information directly from the involved arterial sites. Experience has shown that the results of duplex scanning are comparable with those of arteriography. The addition of color Doppler imaging to standard duplex scanning expedites the examination by helping to identify vessels and localize flow disturbances. However, precise classification of disease severity still requires spectral waveform analysis. Initial screening of patients with duplex scanning can determine the severity of arterial occlusive disease, the location of the lesions, and which interventional techniques are most appropriate. Arteriography can then be reserved for those patients who are being considered for therapeutic interventions. Duplex scanning has become the primary diagnostic test for follow-up of patients after radiological or surgical procedures and should be considered as an essential component of care for patients with infrainguinal bypass grafts. It has also proven to be valuable for intraoperative assessment and the initial evaluation of suspected vascular trauma in the extremities. Finally, new applications such as compression therapy for pseudoaneurysms continue to evolve and expand the role of duplex scanning in the management of patients with vascular problems.