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Ency. home > Test > L > Lower extremity venography

Lower extremity venography   

Overview | Risks | Results

Alternative names:

Phlebography; Venogram

Definition:

The veins are the blood vessels that return the blood to the heart. They do not have the pressure in them that arteries do, so their walls are thinner and there is not as much bleeding when they are punctured. The veins are not normally seen in an X-ray, so a contrast material is injected into the vein to make it visible. In this test, the contrast material is injected into the vein of the affected extremity.

X-rays are a form of electromagnetic radiation (like radio waves or light). The wave length is very short and is capable of penetrating the body and producing a shadow picture of the structures inside the body. Some of the X-rays are absorbed by body tissues, while other X-rays will pass through. The denser tissues, such as bone, appear on the film as white. Less dense tissues, such as muscles, appear as gray; and air on the X-ray appears as black.

How the Test is Performed

This test is done in the hospital. You will be asked to lie on the X-ray table. A vein is punctured in the foot of the affected leg and an intravenous catheter (a short flexible tube) is inserted.

A tourniquet may be placed on your leg so that the contrast medium will flow up the deeper veins. The contrast material is injected into the vein through the catheter, and X-rays are taken following the contrast material through the extremity. The catheter is then withdrawn, and the puncture site is bandaged.

How to Prepare for the Test

Adults:
Advise the health care provider if you are pregnant. Mention any allergic reactions to X-ray contrast material, iodine substance, and any thing else. You may need to sign a consent form. You will be given a gown to put on.

Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experience, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:

How the Test will Feel

The X-ray table is hard and cold; you may ask for a blanket or pillow. There is a sharp poke when the intravenous catheter is inserted. As the dye is injected, a burning sensation may occur. There may be tenderness and bruising at the site of the injection after the test.

Why the Test is Performed

The test is used to identify and locate thrombi (blood clots) in the veins of the extremity that is affected. Since the development of ultrasound, it is rarely performed.

Ency. home > Test > L > Lower extremity venography

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