Renal arteriography is a test to examine the blood vessels of the kidneys, using contrast material and x-rays. See also renal venogram.

These arteries are difficult to fully examine on an ordinary x-ray, so a contrast material is injected into one or more arteries so they may be seen and evaluated.

This test is done in the hospital. You will be asked to lie on the x-ray table. The area where the contrast medium will be introduced is shaved and cleansed. The site is usually in the leg. A local anesthetic is given and a needle is inserted into the artery.

A catheter (a long, narrow, flexible tube) is introduced over a wire into the artery. The catheter is threaded through the main vessels of the pelvis, up to the abdominal aorta (which provides blood from the heart to the lower body). This procedure is monitored by a fluoroscope (a special x-ray that projects the images on a TV monitor).

The contrast medium is then injected into the renal artery through the catheter, and images are taken. The catheter is kept open by flushing it periodically with a saline solution containing heparin (a blood thinner), which will keep the blood in the catheter from clotting.

After the x-rays are taken, the catheter is withdrawn. Pressure is immediately applied to the leg at the site of insertion for 10 to 15 minutes or more to stop the bleeding. After that time, the area is checked and a bandage is applied. The leg should be kept straight for an additional 6 hours after the procedure.

Digital Subtraction Angiography (DSI) uses a computer to "subtract" out the bones and tissues in the region so that only the vessels filled with contrast are seen.

Tell the health care provider if you are pregnant and if you have ever had any bleeding problems. Report any allergic reactions you have ever had, especially those you have had to x-ray contrast material or any iodine substance.

You must sign a consent form. Do not eat or drink anything for 8 hours before the test. You will be given a hospital gown to wear and asked to remove all jewelry. You may be given a sedative or pain pill before the procedure.

The x-ray table is hard and cold; you may ask for a blanket or pillow. There is a sting when the anesthetic is given. This does not numb the artery so there will be brief, sharp pain as the catheter is inserted. There is a feeling of pressure as the catheter is advanced.

As the dye is injected, there may be a warm or burning sensation. There may be slight tenderness and bruising at the site of the injection after the test.

The test is done to evaluate the blood vessels that feed the kidney. The test may detect stenosis (narrowing of the blood vessel), blood clots, or aneurysm (a widening of the vein or artery). The test may help evaluate kidney disease or failure, tumors, or kidney function.

It is often used to evaluate donors and recipients before transplantation of a kidney to determine the number of arteries and veins on each kidney.

Some vascular tumors in the kidney can be partially treated by embolizing (placing material in the vessel so it clots and becomes occluded) the feeding arteries.