CT angiography of the lower extremities.

CT angiography (CTA) of the lower extremities has evolved into a robust noninvasive angiographic technique with the advent of 16 and 64 multidetector computed tomographic systems and advances in system design. CTA has displaced conventional catheter arteriography in a large range of applications and is predominantly used in the evaluation of atherosclerotic peripheral arterial occlusive disease in symptomatic patients who are candidates for intervention. Other disease entities including atheroembolism and thromboembolism, aneurysmal disease, and arteritides including Buerger disease and Takayasu arteritis can be precisely evaluated by CTA. Particular applications include arterial vascular mapping for free flap transfers and fibular grafts and evaluation of trauma, before and following orthopedic and plastic surgery interventions. Patients with intravascular stents and arterial bypass grafts who usually undergo serial evaluation by noninvasive, nonangiographic testing are potential candidates for angiographic study when clinical findings of noninvasive tests are in disagreement. The key to a successful clinical application is in understanding how to acquire, display, and interpret high-quality CTA in diverse clinical circumstances.