Medical scanning using MRI, CT and PET imaging machines has grown into a $100 billion dollar a year business with 95 million scans done each year. Still, some big questions remain: Are they helpful and are they safe?
The answer revealed by recent research studies is that 20% to 50% of the procedures reviewed should never have been done because their results did not help diagnose ailments or treat patients.
Part of the problem is that older machines may create bad scans, which may lead to false or poor diagnostic data. According to Dr. Gary Glazer, the chairman of radiology at Stanford University, a scan done on a 10-year-old machine versus a new one will have significant differences in the quality of the image. Even a scan done on the latest equipment may not have been done correctly or correctly read by a qualified doctor.
In addition, the field is mostly unregulated. While imaging centers can choose to become accredited by the American College of Radiology, not many do. This will change in 2012 when a Medicare law goes into effect requiring accreditation.
Another concern is that a growing number of doctors are referring patients to imaging centers owned by the doctors themselves. Studies have found up to 3.2 times as many scans are ordered by those docs. So, is a scan being requested by the doc because it’s necessary or because it’s profitable?
The final issue is the amount of radiation that you are exposed to when a scan is done. A study of hospital patients showed that they had been exposed to 45 millisieverts (mSv) of radiation. Since the typical X-ray delivers .02 mSv, 12% of patients had been exposed to more that twice that amount.
With all these concerns, you need to ask your doc some questions before you agree to have a scan done, including how old the machine is and the qualifications of the scanner and the interpreter.
(Reported The Virginian Pilot, 2009, Article by Gina Kolata, New York Times News Service)