The Disadvantages of CT Scans
-
Radiation Exposure
-
During CT, patients are exposed to about 10 millisieverts of radiation. According to the U.S. Food and Drug Administration, that risk amounts to a one in 2,000 chance of developing a fatal cancer, which is much lower than the one in five chance of developing fatal cancer from natural sources of radiation.
In particular, pregnant women are at a disadvantage because of the potential risks of radiation exposure to the developing fetus, including birth defects. For that reason, CT is not recommended for pregnant women. Similarly, the test is not recommended for children because, over time, radiation exposure can accumulate and increase the risk of developing cancer.
Allergic Reaction
-
An allergic reaction to dyes administered to patients during CT to highlight areas of the body is possible. While rare, these reactions may include mild itching, hives, and, in more serious cases, shortness of breath or swelling, according to the National Cancer Institute. Patients with a history of heart disease, asthma, diabetes, kidney disease, or thyroid disorder are at greatest risk, the Mayo Clinic notes.
Abnormal Results
-
CT may yield abnormal test results. This can be concerning for patients and prompt doctors to order additional follow-up tests that can be expensive, invasive, and uncomfortable and present additional risks for patients.
Warning
-
Full-body CT should not be used as a preventative-disease screening tool. There is no scientific evidence to support the benefits of full-body CT in healthy individuals with no symptoms of disease, the FDA notes.
-