CT Scan (General)
(Computed Tomography Scan; Computed Axial Tomography; CAT Scan)
by Krisha McCoy, MS
A CT scan uses x-ray technology to take multiple views of the inside of the body. Compared to regular x-rays, a CT scan can take clearer and more detailed images of organs, bone, soft tissue, blood vessels, and other parts of the body.
Reasons for test TOP
Some of the primary uses for CT scans include:
Possible Complications TOP
Complications are rare, but no procedure is completely free of risk. If you are planning to have a CT scan, your doctor will review a list of possible complications. These may include:
Factors that may increase the risk of complications include:
You are exposed to some radiation during a CT scan. Radiation exposure can increase your lifetime risk of cancer. This risk increases the more times you are exposed to radiation. Radiation exposure is more concerning for pregnant women and children. CT scans are usually not advised for pregnant women.
Be sure to discuss these risks with your doctor before the test.
What to Expect TOP
Prior to Test
Description of the Test
You will lie (usually on your back) on a movable bed. The bed will slide into the donut-shaped CT scanner. Depending on the type of scan, an IV line may be placed in your hand or arm. A saline solution and contrast material may be injected into your vein during the test. The technologist will leave the room. You will be given directions using an intercom. The machine will take a series of pictures of the area of your body that is being studied. Your bed may move slightly between pictures.
After Test TOP
You will need to wait for the technician to review your images. In some cases, more images will need to be taken.
How Long Will It Take? TOP
About 10-15 minutes, depending on how many pictures are needed.
Will It Hurt? TOP
You may feel warm and flushed if contrast material is injected into your vein. Otherwise, you should feel no pain.
The CT images will be sent to a radiologist who will analyze them. Your doctor will receive the results and discuss them with you.
Radiological Society of North America
US Food and Drug Administration
Canadian Association of Radiologists
Canadian Radiation Protection Association
Computed tomography (CT)—body. Radiological Society of North America website. Available at:
...(Click grey area to select URL)
Updated September 23, 2014. Accessed March 14, 2016.
Radiation-emitting products: computed tomography (CT). US Food and Drug Administration website. Available at:
...(Click grey area to select URL)
Updated August 7, 2014. Accessed March 14, 2016.
Last reviewed March 2017 by EBSCO Medical Review Board Marcie L. Sidman, MD
Last Updated: 3/18/2013
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