But many parents and doctors are asking whether kids are getting too much radiation from some tests.
About 2 years ago Andrew Beck learned he had scoliosis, a curvature of the spine.
That meant a back brace and frequent tests to check his progress.
In 2 years he's had about half a dozen x-rays and CT scans, and some were repeated because the first images weren't usable.
According to a recent study, the average child gets 7 radiation-based scans before the age of 18. Each one raises the cancer risk a tiny bit.
"Radiation early in life is going to affect organs that are actively growing," said Dr. Diego Jaramillo, radiologist-in-chief at The Children's Hospital of Philadelphia. "If you are 5 when you get a CT scan, you have 80 or 90 years to carry on the damage."
Dr. Jaramillo says radiologists and equipment-makers launched the Image Gently campaign to reduce exposure.
Some machines are being reprogrammed to deliver smaller doses, and doctors are rethinking which tests to order. They are using CT scans less and non-radiation tests like MRI and ultrasound more.
About 10 years ago, CT scans were the standard for appendicitis.
"We started realizing we would get the same information, or better information, for children with ultrasound," said Dr. Jaramillo.
And there's also new technology, like EOS, which uses about 1/7 the radiation.
"Instead of getting a whole beam of x-rays, it just has a very thin beam," Dr. Jaramillo said.
And it takes the front and side views in one pass.
Dr. Jaramillo says parents should ask some questions, including: Is the test necessary? And can another test be used to come to the same answer?
He says most medical centers will work with parents on getting the right test for a child while keeping radiation to a minimum.
