Angiography is an imaging technique used to visualize the inside of blood vessels. Contrast material is injected into the vessel using sterile technique and imaged using x-ray. The contrast, often referred to as "dye", causes the vessels to be visible on x-ray, and is useful for locating blockages or malformations in the arteries and veins. Access to the blood vessel is most commonly gained through the femoral artery in the groin area where it lies relatively near the surface. Using a guide wire and catheter (a thin flexible tube), dye is injected into the targeted blood vessel. Images are taken, usually 2-3 frames per second, and using a technique called Digital Subtraction Angiography (DSA), the overlying image of bones and organs are "canceled out" leaving only the vessels.
What to expect
You will be awake and alert, though you may be given medication to help you relax. Prior to the procedure, the femoral artery area (groin area) is cleaned with a scrub solution. After sterile draping is applied, the area is numbed with local anesthetic. The radiologist will use a needle to gain access to the artery. A guide wire will be threaded through the needle and advanced to the target area using fluoroscopic (x-ray) guidance. Once the guide wire is in the correct position the catheter is advanced down the wire and the wire removed. Because the area is numb, you shouldn't feel the guide wire or catheter. Contrast is injected through the catheter while images are made. It is important to remain motionless during imaging to ensure the best images possible. When the dye is administered, you may feel warm and also the urge to urinate. When the radiologist is done imaging all necessary areas, the catheter will be removed and hand held pressure applied for about 15 minutes to stop bleeding. After the procedure you will need to lie flat for 4-6 to allow the artery to heal. The radiologist will interpret the images and send a signed report to your ordering physician.