DENVER (CBS4) – A lot of parents turn to imaging procedures like CT scans or MRIs to make sure their children are healthy, but it turns out those very tests could be putting them in harm’s way later in life.

Grace Hickson’s great-grandson Andre had his first X-ray when he was 1 1/2 years old.

“He couldn’t breathe and I took him to another doctor and they X-rayed and that’s when they told me he had pneumonia,” Hickson said.

A new study in the journal “Pediatrics” finds the number of children who have undergone diagnostic imaging scans, including X-rays, MRIs, CT scans and ultrasounds has increased significantly over the past nine years. Higher radiation procedures, like CT scans rose 34 percent during the study.

The findings raise concern because other studies have linked radiation exposure to increased risk of cancer.

“Children are all growing, so that means their cells are all rapidly replicating, so that means they are more at risk for radiation than an adult,” pediatrician Dr. Jessica Sessions with the Ryan Center said.

Imaging procedures with higher amounts of radiation were most frequently performed in the hospital and emergency room settings.

Researchers didn’t determine how much of the imaging was truly necessary. Health experts say parents should question their child’s doctor before agreeing to any scan.

“Ask them, ‘Well, how much radiation is involved,’ and ‘Is the test really necessary?’ ” Sessions said.

Hickson says she was aware of the radiation risk, but felt the test needed to be done.

“Unfortunately a lot of time children have to have X-rays to find out exactly what’s wrong,” she said.

She says she tries to do whatever is best for Andre’s health.

The study found the three most common reasons for the scans were abdominal pain, headache and head injury.