CDI Miami | Thursday February 16, 2017

Doctor’s Orders: Is it the right time to get a CT Scan?

A new report in tomorrow’s issues of the New England Journal of Medicine raises serious concerns about the use, and overuse of CT scanning. While individual risks of developing cancer from a CT scan are relatively low, the researchers ventured that repeated exposure to radiation from diagnostic imaging could potentially threaten patient populations if left unchecked.

How can you tell if it is time to get a CT scan?

In a traditional X-ray – a chest X-ray, for example – radiation goes through you from one side to the other with 3-D information ultimately projected onto a two-dimensional picture. With a CT scan, an X-ray tube rotates around the patient and presents the results to you as a three-dinensional picture. The advantage is that it’s much more sensitive, is high resolution, and offers much more anatomically specific information with great detail.

When should you get a CT scan?

If you think something is desperately wrong with you and you need an immediate answer. For example, if you have sudden severe abdominal pain or an intense headache that came out of nowhere.

CT scans are incredibly accurate, and can help you determine the source of your pain. For instance, CT scans can prevent false-diagnosis of appendicitis, having reduced false positives by nearly 20%.

Are their risks involved in CT scanning?

There is very minimal risk in CT scanning.  For children, the risk of developing a fatal cancer from radiation exposure is somewhere around 1 in 500 or 1 in 1,000 – the older you get, the lower the risk becomes. For an adult, the risk is around 1 in 2,000. At this point, people believe there is a linear relationship between the dose and risk in half.

Are there alternatives to CT scanning that patients should know about or ask their doctors?

You can always ask if there are ways to find out the answer without using radiation. Using ultrasound, for example, or doing an MRI scan. Those don’t use ionizing radiation, so there is virtually no risk. If a child is getting a scan, the parent can make sure that the radiology technician is using the correct pediatric doses.

Are CT scans useful for asymptomatic patients?

CT scans are not necessary for asymptomatic patients. Scans should only be used when there is a suspicion of an illness or disorder. There are still studies determining the risk profile of scans on different populations.