What is angiography?

Angiography  is the X-ray imaging of blood vessels using contrast agents injected into the bloodstream. A thin plastic tube (catheter) is placed directly in your blood vessel, usually an artery but other times a vein. The contrast or radio-dye is pushed into the blood vessels through the catheter while a continually running X-ray looks at the place of concern or interest.

The images recorded as the dye runs through the blood vessels in view are called angiograms. Angiography gives information about blood vessel abnormalities, such as narrowing, blockage, inflammation, abnormal widening and bleeding. Angiography is also used to guide procedures that treat blood vessel abnormalities. If the artery is narrowed, a tiny balloon can be inflated (and occasionally a piece of metal tubing called a ‘stent’ can be inserted) to widen the artery and restore normal blood flow. This procedure is called angioplasty.

Angiography is also used to guide procedures where abnormal blood vessels need to be blocked off if they are bleeding (called ‘embolisation’), or as part of other medical investigations or surgical treatments.

Angiograms can also be done using computed tomography (CT) or by magnetic resonance imaging (MRI) again using a contrast agent in the blood. CT or MRI angiography only show the appearances of the blood vessel and cannot be used for treatment procedures.