Duplex ultrasound
Vascular ultrasound; Peripheral vascular ultrasound
A duplex ultrasound is a test to see how blood moves through your arteries and veins.
Ultrasound
Ultrasound uses high-frequency sound waves to make images of organs and structures inside the body.
How the Test is Performed
A duplex ultrasound combines:
- Traditional ultrasound: This uses sound waves that bounce off blood vessels to create pictures.
- Doppler ultrasound: This records sound waves reflecting off moving objects, such as blood, to measure their speed and other aspects of how they flow.
There are different types of duplex ultrasound exams. Some include:
- Arterial and venous duplex ultrasound of the abdomen. This test examines blood vessels and blood flow in the abdominal area.
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Carotid duplex ultrasound
looks at the carotid artery in the neck.
Carotid duplex ultrasound
Carotid duplex is an ultrasound test that shows how well blood is flowing through the carotid arteries. The carotid arteries are located in the neck...
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Duplex ultrasound of the extremities
looks at the arms or legs.
Duplex ultrasound of the extremities
This test uses ultrasound to look at the blood flow in the large arteries and veins in the arms and legs.
- Renal duplex ultrasound examines the kidneys and their blood vessels.
You may need to wear a medical gown. You will lie down on a table, and the ultrasound technician will spread a gel over the area being tested. The gel helps the sound waves get into your tissues.
A wand, called a transducer, is moved over the area being tested. This wand sends out the sound waves. A computer measures how the sound waves reflect back, and changes the sound waves into pictures. The Doppler creates a "swishing" sound, which is the sound of your blood moving through the arteries and veins.
You need to stay still during the exam. You may be asked to lie in different body positions, or to take a deep breath and hold it.
Sometimes during a duplex ultrasound of the legs , the health care provider may calculate an ankle-brachial (ABI) index. You will need to wear blood pressure cuffs on your arms and legs for this test.
Duplex ultrasound of the legs
This test uses ultrasound to look at the blood flow in the large arteries and veins in the arms and legs.
The ABI number is obtained by dividing the blood pressure in the ankle by the blood pressure in the arm. A value of 0.9 or greater is normal.
How to Prepare for the Test
Usually, there is no preparation for this test.
If you are having an ultrasound of your stomach area, you may be asked not to eat or drink after midnight. Tell the person doing the ultrasound exam if you are taking any medicines, such as blood thinners. These might affect the results of the test.
How the Test will Feel
You may feel some pressure as the wand is moved over the body, but there is no discomfort most of the time.
Why the Test is Performed
A duplex ultrasound can show how blood flows to many parts of the body. It can also tell the width of a blood vessel and reveal any blockages. This test is a less invasive option than arteriography and venography .
Venography
Venography for legs is a test used to see the veins in the leg. X-rays are a form of electromagnetic radiation, like visible light is. However, thes...
A duplex ultrasound can help diagnose the following conditions:
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Abdominal aneurysm
Abdominal aneurysm
The aorta is the main blood vessel that supplies blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aor...
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Arterial occlusion
Arterial occlusion
Acute arterial occlusion of the kidney is a sudden, severe blockage of the artery that supplies blood to the kidney.
- Blood clot
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Carotid occlusive disease (See:
Carotid duplex
)
Carotid duplex
Carotid duplex is an ultrasound test that shows how well blood is flowing through the carotid arteries. The carotid arteries are located in the neck...
-
Renal vascular disease
Renal vascular disease
Renal vein thrombosis is a blood clot that develops in the vein that drains blood from the kidney.
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Varicose veins
Varicose veins
Varicose veins are swollen, twisted, and enlarged veins that you can see under the skin. They are often red or blue in color. They most often appea...
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Venous insufficiency
Venous insufficiency
Venous insufficiency is a condition in which the veins have problems sending blood from the legs back to the heart.
A renal duplex ultrasound can also be used after transplant surgery. This shows how well a new kidney is working.
Normal Results
A normal result is normal blood flow through the veins and arteries. There is normal blood pressure and no sign of a narrowing or blockage of a blood vessel.
What Abnormal Results Mean
An abnormal result depends on the specific area being examined. An abnormal result may be due to a blood clot or plaque buildup in a blood vessel.
Risks
There are no risks.
Considerations
Smoking may change the results of an ultrasound of the arms and legs. This happens because nicotine can cause the arteries to shrink (constrict).
References
Goldstein LB. Approach to cerebrovascular diseases. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 406.
Leon LR, Labropoulos N. Vascular laboratory. In: Cronenwett JL, Johnston KW, eds. Rutherford's Vascular Surgery . 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 18.
Stone PA, Hass SM. Vascular laboratory. In: Cronenwett JL, Johnston KW, eds. Rutherford's Vascular Surgery . 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 16.
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Duplex/doppler ultrasound test - illustration
The duplex/doppler ultrasound test examines the blood flow in the major arteries and veins in the arms and legs. The test uses duplex ultrasonagraphy to visualize the blood flow and doppler ultrasonagraphy provides an audio means to hear the blood flow. This test is done as an alternative to arteriography and venography and may help diagnose abnormalities in an artery or vein.
Duplex/doppler ultrasound test
illustration
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Duplex/doppler ultrasound test - illustration
The duplex/doppler ultrasound test examines the blood flow in the major arteries and veins in the arms and legs. The test uses duplex ultrasonagraphy to visualize the blood flow and doppler ultrasonagraphy provides an audio means to hear the blood flow. This test is done as an alternative to arteriography and venography and may help diagnose abnormalities in an artery or vein.
Duplex/doppler ultrasound test
illustration
Review Date: 6/6/2016
Reviewed By: Deepak Sudheendra, MD, RPVI, Assistant Professor of Interventional Radiology & Surgery at the University of Pennsylvania Perelman School of Medicine, with an expertise in Vascular Interventional Radiology & Surgical Critical Care, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.