Vascular ultrasound is a noninvasive test that uses sound waves to evaluate the body’s circulatory system in the arteries and veins to help identify blockages to blood flow, narrowing of vessels, tumors and congenital vascular malformations. A Doppler ultrasound study – a technique that evaluates blood flow through a blood vessel – is usually part of this exam.  Arterial and Venous ultrasound studies can include the arms, legs, neck and abdomen.