The use of CT has increased exponentially over the last 20 years, and more than 72 million scans were performed in the United States in 2007 compared to only 3 million in 1980.
The use of CT scanning only continues to grow. Doctors are increasing using chest CT to screen for lung cancer, CT based “virtual” colonoscopies to check for colon cancer, CT angiography of the coronary arteries in place of simple exercise stress tests, and CT angiography of the carotid arteries in place of safer duplex ultrasound and MR (magnetic resonance) angiography.
The radiation exposure from a sigle CT scan is equivalent to about 750 chest x-rays.
It is estimated that 0.4% of current cancers in the United States may be from exposure to radiation from CTs performed in the past, and that this may increase to 2% (or 29000 future cancers) as a consequence of 2007 rates of CT usage.
Click here to link Dr Eric Topol’s recent Medscape commentary on the runaway use of CTs.
Click here for a recent Washington Post article on the risk of repeated CT scans in children.
Click here for a statement from the American Academy of Neurology on unnecessary diagnostic testing.
CT can still have some advantages over MR imaging of the brain – it is more readily available and faster in the emergency setting, and can be done in patients who have a contraindication to MR imaging like a pacemaker or other metal implant.
However, it is one of our goals at Monmouth Neuroscience Institute to reduce unnecessary diagnostic testing wherever possible. We strive to avoid doing both CT and MR scans on neurological patients by seeing TIA patients in our outpatient TIA Rapid Evaluation Center(TREC). TREC patients can avoid an emergency room visit and CT scan in favor of an elective MR scan, which not only gives more information, but also avoids an unnecessary dose of radiation.