X-rays and CT scans use radiation to make their pretty pictures. We put up with the small risk of radiation because there's a pretty big benefit to letting your doctor see inside you. Some scans, however, are unnecessary, and some give bigger radiation doses than you might realize. Here's how to know when to say yes to the scan, and when to ask for a second opinion. A single x-ray isn't going to kill you, but lifetime exposure matters. Somebody who gets frequent scans, especially high-dose scans (like some types of CT scans) will have a slightly increased risk of cancer. A new report from Consumer Reports provides a roundup of the radiation doses from different scans, and why you might want to second-guess your doctor in some cases. First, here's the rundown on how much radiation to expect from each type of scan: Ultrasounds and MRIs don't use any radiation. Mammograms use low doses of radiation. (Laws exist to limit your radiation dose from mammograms.) X-rays use a radiation dose that is "minimal to medium," according to Consumer Reports. Fluoroscopy, a sort of video x-ray, gives higher doses than regular x-rays. CT scans can vary from minimal to very high doses, up to the equivalent of 200 x-rays. PET scans involve putting a small amount of radioactive tracer material in your body. These range from medium to high exposure. Not all scans are medically necessary. Some are repeats of a scan that was previously done and didn't need to be repeated, some result from a physician wanting to be sure of a diagnosis to avoid liability, and not to be too cynical, but some result from a financial conflict of interest when a doctor owns an in-office machine or has invested in a radiology clinic. Some experts say up to one third of CT scans are unnecessary. And unnecessary scans often lead to more scans, to confirm and monitor incidental findings that may not actually be a problem. Consumer Reports suggests asking for a second opinion if you know that your doctor owns a CT scanner (yes, it's okay to ask about financial conflicts of interest), or if they recommend a whole-body CT scan or a 3D dental scan. Otherwise, you can keep your radiation exposure low by asking questions when a doctor orders a scan, including: Why are you ordering this test, and what would happen if I don't get it? How much radiation will I be exposed to? Is there an alternative scan that uses less radiation? Are we using the lowest effective dose? Have you taken my body size into account? Did you check whether I've already had this scan recently? For more questions to ask, and the nitty-gritty on just how much radiation dosage you get from different scans, read the full article at Consumer Reports. Source
