CT Angiography  Published On 07/11/2011  CT (computed
tomography) angiography (CTA) is an examination that uses x-rays
to visualize blood flow in arterial vessels throughout the body,
from arteries serving the brain to those bringing blood to the
lungs, kidneys, and the arms and legs. CT combines the use of
x-rays with computerized analysis of the images. Beams of x-rays
are passed from a rotating device through the area of interest
in the patient's body from several different angles so as to
create cross-sectional images, which then are assembled by
computer into a three-dimensional picture of the area being
studied. Compared to catheter angiography, which involves
placement of a catheter and injecting contrast material into an
artery, CTA is a much less invasive and a more patient-friendly
procedure; contrast material is injected into a peripheral vein
rather than an artery. This exam has been used to screen large
numbers of individuals for arterial disease. Most patients have
CT angiography without being a