Testing: Computer (Assisted) Tomography (CT)

Computerized Tomography (CT) machines use a series of X-rays to view the insides of a patient’s body. The images show cross-sectional slices of your body, as if you were looking down through the body from the top of your head. These cross-sections represent a very thin layer of your body, and there are hundreds of “slices” per scan, so doctors can examine your internal organs very thoroughly.

The CT scanner itself is composed of a moving table, on which the patient lies, and a spinning X-ray machine. The portion that spins takes the images and transfers them to a computer for a technician to view and analyze.

In some cases, the doctors want to enhance the images. They accomplish this by injecting patients with a “contrast” agent, or dye, such as iodine. This will “dye” your organs or blood vessels so that doctors can see them clearly on the scan output. The dyes have generally mild symptoms. For instance, the iodine may make a patient feel very warm when it is injected, but the feeling goes away shortly after the scan.

If you’ve had any adverse reactions to iodine in the past, you should alert your physician prior to the scan. If you feel unusual after the contrast is injected, please alert the health care professionals monitoring your scan and they will take care of you.

Pregnant women should not have a CT scan, as the X-rays could damage the baby.

Why use a CT Scan?

CT scans are better at viewing bones than other scanning technologies, such as MRI.

Similar Tests

MRI scans, gallium scans, and PET scans all provide similar data for the diagnosis of cancer.

Photo by Braegel