CT Scans Raise Cancer Risk in Children

A CT scan may not be the best way to evaluate traumatic brain injury (TBI) in a child, especially if he or she had a previous scan. New research indicates that CT scans pose potential cancer risks from associated ionizing radiation, particularly to children, who are more radiosensitive than adults. The 20-year retrospective study, funded by the U.S. National Cancer Institute and the U.K. Department of Health, was published online in the Lancet today.

Researchers said the use of CT scans in children to deliver cumulative doses of about 50 mGy might almost triple the risk of leukemia, and doses of about 60 mGy might triple the risk of brain cancer. Because these cancers are relatively rare, the cumulative absolute risks are small: In the 10 years after the first scan for patients younger than age 10, one excess case of leukemia and one excess case of brain tumor per 10,000 head CT scans is estimated to occur. Clinical benefits should outweigh the small absolute risks, but radiation doses from CT scans ought to be kept as low as possible, and alternative procedures that do not involve ionizing radiation should be considered.

For information about other methods for evaluating children with possible TBI, see the Textbook of Traumatic Brain Injury, Second
Edition, available from American Psychiatric Publishing, here.

(Image: Marcel Mooij/Shutterstock.com)