Cardiovascular Imaging Center of Daly City

Leg Arterial Exam

Ultrasound imaging, also called ultrasound scanning or sonography, involves exposing part of the body to high-frequency sound waves to produce pictures of the inside of the body. Ultrasound exams do not use ionizing radiation (x-ray). Because ultrasound images are captured in real-time, they can show the structure and movement of the body's internal organs, as well as blood flowing through blood vessels.

Ultrasound imaging is usually a painless medical test that helps physicians diagnose and treat medical conditions.

Vascular ultrasound provides pictures of the body's veins and arteries.

A Doppler ultrasound study may be part of a vascular ultrasound examination.

Doppler ultrasound is a special ultrasound technique that evaluates blood as it flows through a blood vessel, including the body's major arteries and veins in the abdomen, arms, legs and neck.

Frequently Asked Questions

What are some common uses of the procedure?

Sonography is a useful way of evaluating the body's circulatory system. Vascular ultrasound is performed to:

• help monitor the blood flow to organs and tissues throughout the body
• locate and identify blockages (stenosis) and abnormalities like blood clots, plaque or emboli and help plan for their effective treatment
• determine whether a patient is a good candidate for a procedure such as angioplasty
• to plan or evaluate the success of procedures that graft or bypass blood vessels

Doppler ultrasound images can help the physician to see and evaluate:

• blockages to blood flow (such as clots)
• narrowing of vessels (which may be caused by plaque)
• tumors and congenital malformation

How should I prepare for the procedure?

You should wear comfortable, loose-fitting clothing for your ultrasound exam. You will need to remove all clothing and jewelry in the area to be examined.

You may be asked to wear a gown during the procedure.

If your abdominal vessels are being examined, unless the examination is performed on an urgent basis, it is often best to fast before the procedure.

How is the procedure performed?

For most ultrasound exams, the patient is positioned lying face-up on an examination table that can be tilted or moved.

A clear gel is applied to the area of the body being studied to help the transducer make secure contact with the body and eliminate air pockets between the transducer and the skin. The sonographer (ultrasound technologist) or radiologist then presses the transducer firmly against the skin and sweeps it back and forth over the area of interest.

Doppler sonography is performed using the same transducer.

When the examination is complete, the patient may be asked to dress and wait while the ultrasound images are reviewed. However, the sonographer or radiologist is often able to review the ultrasound images in real-time as they are acquired and the patient can be released immediately.

This ultrasound examination is usually completed within 30 minutes.

What will I experience during and after the procedure?

Most ultrasound examinations are painless, fast and easy.

After you are positioned on the examination table, the radiologist or sonographer will spread some warm gel on your skin and then press the transducer firmly against your body, moving it back and forth over the area of interest until the desired images are captured. There may be varying degrees of discomfort from pressure as the transducer is pressed against the area being examined.

If scanning is performed over an area of tenderness, you may feel pressure or minor pain from the procedure.

If a Doppler ultrasound study is performed, you may actually hear pulse-like sounds that change in pitch as the blood flow is monitored and measured.

Once the imaging is complete, the gel will be wiped off your skin.

After an ultrasound exam, you should be able to resume your normal activities.