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.
Some of the primary uses for CT scans include:
Problems from the procedure are rare, but all procedures have some risk. Your doctor will review potential problems, like:
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.
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 the IV 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.
You will need to wait for the technician to review your images. In some cases, more images will need to be taken.
About 10-15 minutes, depending on how many pictures are needed.
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.
Call your doctor if any of these occur:
If you think you have an emergency, call for emergency medical services right away.
NIH Clinical Center
Radiology Info—Radiological Society of North America
Canadian Association of Radiologists
Canadian Radiation Protection Association
Computed tomography (CT)—body. Radiology Info—Radiological Society of North America website. Available at: http://www.radiologyinfo.org/en/info.cfm?pg=bodyct&bhcp=1. Updated March 16, 2016. Accessed March 13, 2018.
Radiation-emitting products: computed tomography (CT). US Food & Drug Administration website. Available at: https://www.fda.gov/Radiation-EmittingProducts/RadiationEmittingProductsandProcedures/MedicalImaging/MedicalX-Rays/ucm115317.htm. Updated March 7, 2018. Accessed March 13, 2018.
Last reviewed March 2018 by EBSCO Medical Review Board Marcie L. Sidman, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.