Ultrasound examination of the arteries of the lower extremities is a common method used in vascular surgery to examine the arteries of the lower extremities. The method is simple, non-invasive, relatively inexpensive and easy to perform. When performing lower extremity artery examination, the diameter of the blood vessel, the direction of blood flow, and the presence of stenosis or plaque in the blood vessel can be clarified by ultrasound. In some patients with atherosclerosis, the location and size of the plaque in the artery, as well as the number of plaques, can be clarified by ultrasonography, so that the blood flow and stenosis of the lower extremity as well as the distal vessels can be evaluated. In some special cases, lower extremity artery ultrasound can also be used to clarify the presence of lower extremity artery malformations, arteriovenous fistulas, lower extremity artery entrapment or aneurysms, etc. The ultrasound examination of the arteries of the lower extremities can also be used to perform arterial puncture or arterial drug delivery. Therefore, lower extremity artery ultrasound is a multifunctional examination method.