




Lower Extremity Arterial 

Doppler ultrasonography of the lower extremity arteries is a valuable technique, although it is less frequently indicated for peripheral arterial disease than for deep vein thrombosis or varicose veins. Ultrasonography can diagnose stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries. To perform Doppler ultrasonography of the lower extremity arteries, the operator should be familiar with the arterial anatomy of the lower extremities, basic scanning techniques, and the parameters used in color and pulsed-wave Doppler ultrasonography.

Using gray-scale technique, a significant atherosclerotic vascular lesion can be detected only by thickening of the vessel wall or segmental narrowing of the lumen (which usually represents plaque or mural thrombus). Aneurysms and intimal flaps may also be identified.

Lower-extremity peripheral arterial disease (LEPAD) is often diagnosed by using US, which depicts a change in the flow pattern on Doppler spectrum imaging. Proximal to the lesion, the flow pattern is normal. At the stenosis, the peak systolic velocity increases in proportion to the degree of stenosis. The diastolic portion of the Doppler waveform depends on the artery distal to the lesion and the severity of the lesion. Diastolic flow may be significantly increased or absent. Systolic velocity distal to the lesion is equal or lower than the velocity proximal to the stenosis.

The absence of a flow signal may represent occlusion, vascular calcifications, or technical error. Thrombosis is usually seen as echogenic material in the artery. Large collateral branches are likely to indicate high-grade stenosis or more distal occlusion.

A thorough examination provides information about the entire common femoral, superficial femoral, and popliteal arteries. Examination of the deep femoral and tibial vessels is usually limited.

Multiple published studies evaluated the femoropopliteal segment. The reported sensitivity was more than 85%, and the specificity was more than 92% in detecting segmental arterial lesions.

Lower Extremity Venous

& Venous Insufficiency   



Venous ultrasound provides pictures of the veins throughout the body.




A venous ultrasound study is also performed to determine the cause of long-standing leg swelling. In people with a common condition called "varicose veins", the valves that normally keep blood flowing back to the heart may be damaged, and venous ultrasound can help identify the damaged valves and abnormal blood flow and aid in guiding placement of a needle or catheter into a vein. Sonography can help locate the exact site of the vein and avoid complications, such as bleeding or damage to a nearby nerve or artery also map out the veins in the leg or arm so that pieces of vein may be removed and used to bypass a narrowed or blocked blood vessel. An example is using portions of vein from the leg to surgically bypass narrowed heart (coronary) arteries.