As I’ve written, I’m concerned about excessive radiation received by kids in CT scans. Part of the problem is too many scans. Another problem is the failure of radiologists to reduce the power settings on the CT scanner when imaging kids. The Image Gently initiative from The Alliance for Radiation Safety in Pediatric Imaging is doing a great job of raising awareness and providing resources for physicians.
Here’s what they tell physicians:
There’s no question: CT helps us saves kids’ lives!
But, when we image, radiation matters!
Children are more sensitive to radiation.
What we do now lasts their lifetimes.
So, when we image, let’s image gently:
More is often not better.
When CT is the right thing to do:
Child size the kVp and mA
One scan (single phase) is often enough
Scan only the indicated area
In any case, a new study indicates some progress. See Study: Radiologists dial back on pediatric CT settings at AuntMinnie.com. The study was designed as a follow-up to a 2001 survey that asked radiologists about pediatric imaging practices.
Almost all respondents said they based tube settings on weight or age, with lower currents for smaller and younger kids. And in general they seem to be making greater adjustments:
For children ages 0 to 4 years, the use of 100 mA or less increased from 42% to 97% for chest CTs and from 28% to 88% for abdominal CTs, with the use of 50 mA or less increasing from 4% to 48% for chest CTs and from 0% to 28% for abdominal CTs. No respondents reported using more than 150 mA, according to the study.
The average mA used decreased between 31 mA and 61 mA across all age groups, but the most marked decreases were observed in the youngest patients: a 54% drop in mA for chest CTs and 44% for abdominal CTs in patients ages 0 to 4 years, and 40% and 37% in patients ages 5 to 8 years.
However, the news actually isn’t terribly reassuring, because the above results reflect only the radiologists who answered the questions. Unfortunately there were many who skipped right past the questions (not to mention the large majority of recipients who didn’t complete the survey at all.)
Despite the high percentage of radiologists using an age- or weight-based protocol, an “alarming” percentage (22%) did not know which protocol they used or skipped the question altogether, according to the researchers. An even higher percentage of respondents (up to 49%) did not know or did not complete the questions regarding tube current and kilovoltage.
What this means to me is that the Image Gently people need to keep working on this issue with physicians. If you are a parent who’s kid is referred for a CT, consult the What Can I Do? section for parents, reprinted below.
Be your child’s advocate. If you only know one thing about CT scans in children, let it be that there is a growing awareness of the opportunities to lower and limit dose in the CT imaging of children without compromising the diagnostic quality. Ask questions and then point your pediatrician or community radiologist to these pages.
- FAQ’s for parents
- Visit RadiologyInfo.org – the informational website for patients
- Parent Information Pamphlet – courtesy of Dr. David Larson and the Children’s Hospital of Denver
- Press Coverage
- An Alarmist Warning
- A thoughtful response to the concern about radiation use in CT scans in children
- Should I get a CT scan?
- An expert in radiation safety gives his opinion about CT use in adults and children.
September 8, 2008