Doctor, Is This CT Scan Necessary?

Should you find yourself in the unfortunate situation of having your child acutely ill in an emergency room or doctor’s office, this may be a good question to remember to ask.

CT (computed tomography) scans revolutionized medicine over the past 20 years. Compared to other imaging technologies, CT scans provide amazing images for diagnosing and treating certain illnesses. And they are pretty fast. Due to these advantages, the numbers of CT scans performed has increased significantly over the years, especially in children.

Too much of a good thing?

There is a downside, however, that is becoming more widely recognized: CT scans use much higher doses of radiation than other imaging techniques. And a recent study (“Parental Knowledge of Potential Cancer Risks from Exposure to Computed Tomography”) in the August 2013 issue of Pediatrics suggests that many parents may not be fully aware of how serious this risk may be.

Most of us are aware that radiation is bad and that you don’t want too much of it. But many of the 742 parents interviewed for this study thought the radiation exposure from a CT scan was similar to the radiation exposure from a regular x-ray. In fact, the radiation exposure from a CT scan is much higher—60 to 80 times greater. And more recent studies are now linking radiation exposure from CT scans with an increased lifetime risk for cancers.

Why are CT scans more dangerous?

  • The radiation exposure is cumulative—that is, the more CT scans a person has done, the greater the risk for negative consequences.
  • Children are especially sensitive to radiation exposure, so particular attention is being paid to how to limit their exposure.

Why do we do CT scans?

Sometimes this imaging technique really is the best way to get a look at a particular part of the body. CT scans are fast, too, and sometimes a quick diagnosis and quick treatment are critical.

Should you refuse all CT scans?

No, not at all. Many times, a CT scan may be the best option for your child. You should, however, be aware of the risks (as I noted above, 60 to 80 times more radiation, for instance) and ask questions.

A frequent scenario that I see is that of a child who has suffered minor head trauma and so has had a physical exam by a physician. This physical examination turns out to be normal, which indicates two things to the doctor: that a head CT is not necessary, and that the child will merely need to be watched and monitored for a period of time. It’s at this point, however, that many parents will ask that their child get a CT scan of the head, “just to be on the safe side.”

Things to consider before your child has a CT scan

Ask the doctor:

  • Will a scan affect the final treatment of my child?
  • Is there another useful imaging technique that doesn’t use so much radiation? For example, sometimes an ultrasound, an x-ray, or an MRI may provide the same information. (A good example is when doctors are looking for appendicitis; oftentimes, an ultrasound of the abdomen will yield important information without requiring any radiation exposure.)
  • Will the CT scan help to avoid surgery or some other potential procedure that has significant risks?
  • Or, in a potentially life-threatening situation, will a CT scan provide particularly rapid information? Sometimes the answer is “yes,” and the benefit of the CT scan outweighs the risk.

But, again, don’t panic. Keep yourself informed and ask lots of questions. 

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