How to Decrease the Dangers of Imaging

  When I was a kid, I had a really cool toy -- the Visible Man. Clear plastic on the outside, the inside was filled with all the detail and fascination of the body's bones and organs. You could literally snap open the man and see exactly how the body was put together. In much the same way, advanced diagnostic imaging allows healthcare providers to get a good look at just about anything that's troubling you. Whether you've got back pain, a bad knee, a strange pain in the side, recurrent severe headaches or any other trouble, you may be asked to get a diagnostic imaging test. At first blush, you may be pleased to hear you're getting one of these high-tech assessments. After all, there's nothing like getting to the root of a vexing problem and figuring out precisely what treatment will work. You should know, however, that there are a few issues to worry about. Many advanced diagnostic imaging tests give you a hefty dose of radiation, which is additive. That means that once you've been exposed to radiation, it doesn't "go away." It accumulates, giving you a larger and larger "total life" radiation dose as you age and are exposed to additional sources. According to research published in the “Journal of the American Medical Association” on June 13, 2012, the average dose of radiation given with medical imaging increased by 3.2% annually from 1996 to 2010. The proportion of patients exposed to high or very high doses of radiation just about doubled during the same time frame.

The annual per person radiation dose given by computerized tomography (CT) quadrupled. And the proportion of people exposed to high and very high radiation doses went up with age. People 65 and older had roughly a 10% chance of being exposed to significantly high radiation as of 2010. (Eleven percent were exposed to high doses and 7.3% were exposed to very high doses).  Lead author Rebeca Smith-Bindman, M.D., of the University of California, San Francisco, used data from the nonprofit academic organization National Research Council  to estimate the number of cancers expected to develop from exposure to high-dose diagnostic imaging. Their results suggested that 1 in 270 women and 1 in 600 men undergoing CT heart scans at the age of 40 will develop cancer related to that scan. (High levels of radiation exposure can raise your risk of cancer, leukemia and related diseases.) Even lower-dose imaging procedures carry risks, especially in children. According to the study , the number of CT exams tripled during the 15 year period of the study and the use of magnetic resonance imaging (MRI) quadrupled. By the way, the research was done in an "integrated health care system," or health maintenance organization (HMO), which is typically associated with lower usage of advanced technology due to its team management approach and the fact that it doesn't charge members on a fee-for-service basis. So one can assume the data -- both in term of total radiation exposure and usage -- would be higher in a fee-for-service system.

Other research estimates that approximately 29,000 future cancers could be related to CT scans performed in a single year -- 2007 --   in the United States. About 35 percent of these cancers were projected to be related to scans performed on patients 35 to 54 years old, and 15 percent related to scans performed in children. Smith-Bindman told Medscape that we need to fund comparative effectiveness research to help understand the pros and cons of imaging and "when it may potentially lead to more harm than good." No question about it, there are times when advanced diagnostic imaging may be in your best interest. By pinpointing a serious diagnosis it can sometimes make a critical difference in the treatment you get.  Yet diagnostic imaging sometimes doesn't give you a clear-cut diagnosis or a definitive way forward in terms of treatment, medication or surgery. Here are some questions that can help you understand what might be best for you: Ask about the alternatives. For example, you can say, "Would it be possible to start with a lower-dose x-ray or radiation-free ultrasound or MRI, and based on what you see, proceed from that?" Sometimes that won't be possible. But it's worth asking.

Ask if you might benefit from waiting a reasonable period of time and coming back to have your problem re-assessed before moving ahead with an advanced diagnostic imaging test. Even though you're probably quite eager to get the problem solved, it may be possible that, by waiting, your health issue will settle down and you can avoid the radiation exposure.  Shop around in your community for a diagnostic center that has late-model, lower-dose versions of the test you need. If you do go forward with a radiation-based test, ask what your precise dose will be and ask that the technician be certain it is based on your size and body weight. Ask specifically if you -- or your family member or child – are getting the absolute lowest dose possible. If your physician wants to use CT scans to check for problems after a diagnosis has already been made, ask about the value of such repeat scanning, especially if it wouldn't result in a significant change in the treatment approach.  Be especially careful if you're petite-sized or if a child or teenager is involved. Find out more about The Alliance for Radiation Safety in Pediatric Imaging’s national Image Gently  campaign. Know that your physician may not be aware of the extent of radiation exposure in the tests he or she is precribing. In a survey, nearly all physicians polled significantly underestimated radiation doses from a CT scan.