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How you prepare
By Mayo Clinic staffHow you prepare for a CT scan depends on which part of your body is being scanned. You may be asked to:
- Take off some or all of your clothing and wear a hospital gown.
- Remove any metal objects, such as a belt or jewelry, which might interfere with image results.
- Stop eating for a few hours before your scan.
Contrast material
A special dye called a contrast material is needed for some CT scans, to help highlight the areas of your body being examined. The contrast material blocks X-rays and appears white on images, which can help emphasize blood vessels, intestines or other structures.
Contrast material can enter your body in a variety of ways:
- Oral. If your esophagus or stomach is being scanned, you may need to swallow a liquid that contains contrast material. This drink may taste unpleasant.
- Injection. Contrast agents can be injected through a vein in your arm, to help view your gallbladder, urinary tract, liver or blood vessels. You may experience a feeling of warmth during the injection or a metallic taste in your mouth.
- Rectal. A contrast material may be inserted in your rectum to help visualize your intestines. This procedure can make you feel bloated and uncomfortable.
Preparing your small child for a scan
If your infant or toddler is having the CT scan, the doctor may recommend a sedative to keep your child calm and still. Movement blurs the images and may lead to inaccurate results. Ask your doctor how best to prepare your child.
- CT — Body. RadiologyInfo.org. http://www.radiologyinfo.org/en/info.cfm?pg=bodyct. Accessed Feb. 24, 2012.
- Smith-Bindman R, et al. Radiation dose associated with common computed tomography examinations and the lifetime attributable risk of cancer. Archives of Internal Medicine. 2009;169:2078.
- Adam A, et al. Grainger & Allison's Diagnostic Radiology. 5th ed. Philadelphia, Pa.: Churchill Livingstone Elsevier; 2008. http://www.mdconsult.com/books/about.do?about=true&eid=4-u1.0-B978-0-443-10163-2..X5001-5&isbn=978-0-443-10163-2&uniqId=319273617-2. Accessed Feb. 24, 2012.
- Contrast materials. RadiologyInfo.org. http://www.radiologyinfo.org/en/safety/index.cfm?pg=sfty_contrast. Accessed Feb. 24, 2012.
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