Vascular ultrasound is the general term for a non-invasive painless test that uses high-frequency sound waves to image blood vessels including arteries and veins.

Lower extremity venous ultrasound is typically performed if a clot in a vein (deep venous thrombosis or DVT) is suspected. The veins in the legs are compressed and the blood flow is assessed to make sure the vein is not clogged. This test is also used to look for chronic venous insufficiency, or leaky valves in the veins, which may cause swelling or edema.

Lower extremity arterial ultrasound may be performed in patients with peripheral arterial disease (PAD), particularly for planning an endovascular procedure or surgery. It is also used after the procedure to monitor stents and grafts for signs of the blockage returning (“restenosis”). If a hematoma develops after a catheterization procedure, arterial ultrasound is also used to check the integrity of the arteries and veins in the groin.