Angiography is a type of radiologicalexamination that is done to image blood vessels in various parts of the body, including the heart, brain and kidneys, so as to determine whether the vessels are diseased, narrowed, enlarged or blocked altogether. After passing a catheter through an artery leading to the body area of interest, a contrast material is injected to highlight the vessels when x-rays are taken.
Nowadays, many catheter angiographic studies have been replaced by less invasive methods, such as computed tomography (CT) angiography and magnetic resonance (MR) angiography, that do not require that a catheter be inserted. Catheter angiography still is widely used in patients who may undergo surgery, angioplasty, or stent placement.
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