Together is a new resource for anyone affected by pediatric cancer - patients and their parents, family members, and friends.Learn More
Computed tomography (CT), also known as computerized tomography or computed axial tomography (CAT), is a test that uses computers and X-rays to produce detailed images of the inside of the body. For pediatric cancer, CT can be used to help diagnose a tumor, provide information about the stage of a cancer, observe response to treatment, guide procedures such as a biopsy, and help plan radiation treatments.
During a CT scan, multiple images are taken from several different angles, usually in a very short time, as the part of the body (such as the head, chest, abdomen or the entire body) is scanned. The cross-sectional images can be viewed on a computer monitor, printed on film, or transferred to a CD or DVD. They can be reformatted in multiple planes and can produce three-dimensional images.
Each pediatric center has its own procedures, but generally a patient can expect the following:
CT images of internal organs, bones, soft tissue, and blood vessels provide more detailed pictures than traditional X-rays, particularly of soft tissues and blood vessels. The cross-sectional images generated during a CT scan can be reformatted in multiple planes and can produce three-dimensional images. The scans give doctors a wealth of information to help in the diagnosis and treatment of cancer in children.
CT scans use a small amount of radiation that is adjusted according to the child’s age and size. Most centers have elaborate strategies to reduce the dose of radiation, specifically designed for each child’s individual case.
Radiation exposure from CT scans affects children differently than adults. Children are more sensitive to radiation because of their growing bodies and the rate at which their cells divide. Also, they have a longer life expectancy than adults, so there is more time for radiation-related side effects, which include the very low risk of cancer, to develop. The lifetime risk of cancer from a single CT is small – about 1 case for every 10,000 scans in children, according to the National Institutes of Health. The risk increases when multiple CTs are performed.
Three key questions that parents can ask health care providers regarding radiation safety:
If the CT is medically necessary, experts say the benefits outweigh the small, long-term risk of radiation exposure.
If you have any questions about CT safety, ask your physician.
Reviewed: June 2018