Test Overview
A computed tomography (CT) scan uses
X-rays to make detailed pictures of structures inside
of the body.
During the test, you will lie on a table that is
attached to the CT scanner, which is a large doughnut-shaped machine. The CT
scanner sends X-rays through the body area being studied. Each rotation of the
scanner takes less than a second and provides a picture of a thin slice of the
organ 
or area. All of the pictures are saved as a
group on a computer. They also can be printed.
An iodine dye
(contrast material) is often used to make structures
and organs easier to see on the CT pictures. The dye may be used to check blood
flow, find tumors, and look for other problems. The dye can be used in
different ways. It may be put in a vein (IV) in your
arm, or it may be placed into other parts of your body (such as the rectum or a
joint) to see those areas better. For some types of CT scans you drink the dye.
CT pictures may be taken before and after the dye is used.
A CT
scan can be used to study all parts of your body, such as the chest, belly,
pelvis, or an arm or leg. It can take pictures of body organs, such as the
liver,
pancreas,
intestines,
kidneys,
bladder,
adrenal glands, lungs, and heart. It also can study
blood vessels, bones, and the spinal cord.
Fluoroscopy CT
is a special test that is not widely available. It uses a steady beam of X-rays
to look at movement within the body. It allows the doctor to see your organs
move or to guide a
biopsy needle or other instrument into the right place
inside your body.
