Do CT scans save lives or put people at risk?

The use of computed tomography (CT) scans to detect illness and disease has increased by more than 30% since 2007 in the United States. Yet some fear the practice has an impact on their health due to radiation exposure. But rest assured, CT scans can actually save lives.

Is there radiation exposure during CT scans? 

A recent study projected that nearly 100,000 future cancer cases will be linked to CT scans.  

“A headline figure like this is understandably alarming,” says Dr. Michael Z. Kharouta, a radiation oncologist at Advocate Health Care. “These projections assume there is no completely safe dose of radiation, but many scientists believe the risk associated with the very low doses used in CT scans may be negligible or even zero.” 

Of course, not all scans use the same level of radiation, even if this study treats them equally. A standard diagnostic chest CT scan can have four to five times the amount of radiation than low-dose CT (LDCT) scans.  

“The radiation dose from one LDCT is equivalent to about six months of the natural background radiation we are all exposed to just by living on Earth,” Dr. Kharouta explains. “We must weigh this small, theoretical risk against a very large and proven benefit that CT scans provide, such as detecting illness or injury early.”  

Are there more benefits than risks to getting CT scans? 

Currently, there isn’t hard evidence to say low level radiation from CT scans is dangerous at all. In fact, a study drawing from a large sample size suggests smokers and ex-smokers who received LDCT scans were 20% less likely to die from lung cancer than those who only had a chest x-ray. 

“Lung cancer is the leading cause of cancer death worldwide. It can be very difficult to treat when caught late. But when caught early, thanks to screenings like CT scans, the cure rate can be as high as 80% to 90%. That is not a projection/model; that is a real-world, life-saving benefit of CT scans seen in a large clinical trial.”  

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