We fret about airport scanners, power lines, cell phones and even microwaves. It’s true that we get too much radiation. But it’s not from those sources — it’s from too many medical tests.
Americans get the most medical radiation in the world, even more than folks in other rich countries. The U.S. accounts for half of the most advanced procedures that use radiation, and the average American’s dose has grown six fold over the last couple of decades.
Too much radiation raises the risk of cancer. That risk is growing because people in everyday situations are getting imaging tests far too often. Like the New Hampshire teen who was about to get a CT scan to check for kidney stones until a radiologist, Dr. Steven Birnbaum, discovered he’d already had 14 of these powerful scans for previous episodes. Adding up the total dose, “I was horrified” at the cancer risk it posed, Birnbaum said.
Of the many ways Americans are over tested and over treated, imaging is one of the most common and insidious. CT scans — “super X-rays” that give fast, extremely detailed images — have soared in use over the last decade, often replacing tests that don’t require radiation, such as ultrasound and MRI’s.
Radiation is a hidden danger. Yyou don’t feel it when you get it, and any damage usually doesn’t show up for years. Taken individually, tests that use radiation pose little risk. Over time, though, the dose accumulates.
Doctors don’t keep track of radiation given to their patients. Except for mammograms, there are no federal rules on radiation dose. Children and young women, who are most vulnerable to radiation harm, sometimes get too much at busy imaging centers that don’t adjust doses for each patient’s size.
An eye-opening study that found that U.S. heart attack patients get the radiation equivalent of 850 chest X-rays over the first few days they are in the hospital. Much of it for repeat tests that may not have been needed.
Another study by Columbia University researchers, published in 2007, estimated that in a few decades, as many as 2 percent of all cancers in the U.S. might be due to radiation from CT scans given now. Since previous studies suggest that a third of all tests are unnecessary, 20 million adults and more than 1 million children are needlessly being put at risk, they concluded.
Many studies suggest people are getting too much imaging now. For example, Mayo Clinic reviewed the medical records of 251 people given heart scans in 2007 and found that only a quarter of them were clearly appropriate.
What should patients do?
“You should question everything. Ask questions like, “What’s the dose and why am I getting it?” You should be an informed consumer,” said Dr. Fred Mettler, radiology chief in the New Mexico Veterans Administration health care system. He led a study of health effects after the Chernobyl accident and is a U.S. representative to the United Nations on radiation safety.
He advised challenging “big ticket” tests like CT scans that deliver a lot of radiation to the chest and abdomen. These are places where cancer is likely to develop. “You shouldn’t get too excited about feet and knee scans or X-rays,” Mettler said.
Questions to ask about radiation scans:
Is it truly needed? How will it change my care?
Have you or another doctor done this test on me before?
Are there alternatives like ultrasound or MRI?
How many scans will be done? Could one or two be enough?
Will the dose be adjusted for my gender, age and size? Will lead shields be used to keep radiation away from places it can do harm?
Do you have a financial stake in the machines that will be used?
Can I have a copy of the image and information on the dose?
Dr G’s Comments: My suggestion is take your health into your own hands. Take care of your body and you won’t need to be visiting doctors and getting many needless doses of radiation. If you are in an accident, then this is when you need to ask these questions.