Angiography is the use of a solutionvisibleon X-ray to obtain a contrast X-ray picture o fthe interior of blood vessels. Angiography of arteries (also called arteriography) may be used to detect obstruction due to clots or foreign matter in the bloodstream, or distortions of the vessel wall due to arteriosclerosis, atheroma or aneurysm. The contrast solution is introduced via a catheter (fine tube) that is inserted into a large artery, such as the femoral artery in the groin or the carotid in the neck, and guided through it with X-ray monitoring until it reaches the branch to be examined. X-ray-visible solution is then injected into the branch and a series of X-ray pic-tures taken.
The techniques of angiography may be used for treatment of some blood vessel disorders, and for the administration of drugs directly to particular organs or parts of the body.
Angiography is generally carried out in hospital. Apart from the prick when the catheter is inserted, the procedure is painless. The patient may feel faint or nauseated as the catheter is moved through the artery, and will usually notice a brief flushing sensation as the X-ray-visible, solution is injected. There is a small risk of adverse effects such as, allergy to the solution and damage to the artery when the catheter is inserted and moved.
Angiography can detect the development of clumps of new vessels and other abnormal patterns that suggest tumours, cysts, congenital defects or an injury to any internal organ. Coronary angiography is done to find a blockage in the coronary arteries, which can lead to heart attack. It may be done if you have unstable angina, atypical chest pain, aortic stenosis, or unexplained heart failure. Angiography is used to look at the liver to localise abnormalities, including tumours. This can be particularly useful when planning surgery. This procedure is used to get more exact information after something abnormal has been detected by an CT scan of the head. An example of such abnormality would be bleeding within the brain. During angiography, physicians inject streams of contrast agents or dyes into the area of interest using catheters to create detailed images of the blood vessels in real time. Catheter angiography should be done very cautiously – if at all – in patients who have a tendency to bleed.
Risks of the procedure include the following: