Are CT Scans a Public Health Time Bomb?

The Computed Tomographic Scan (CT Scan) has been the darling of diagnostics for Internal Medicine since its introduction. Conditions that once required an …

The Computed Tomographic Scan (CT Scan) has been the darling of diagnostics for Internal Medicine since its introduction. Conditions that once required an invasive procedure such as a laparoscopy  for diagnosis could now be diagnosed from a seemingly innocuous scan. The CT was non-invasive, fast, and painless and considered completely safe. CT scans have become very routine and accessible in the medical community. However recent research is proving that there is a downside for all this convenience and clinicians must educate their patients on the risk of any radiation exposure to reduce the incidence of future cancers.

Research published this week in the Archives of Internal Medicine estimate that 29,000 future malignancies could occur in the United States because of CT scans performed in 2007 alone. 72 million CT scans were done in 2007. These studies indicate that there is far more radiation in medical CT scans than previously thought. The authors of the recent studies on CT scans and cancer believe the most common radiation-created cancers will be lung and colon cancer and leukemia.

The number of scans has risen from 3 million to nearly 70 million annually in the last 30 years. CT tests have tripled since only 1993. Medicine has always adhered to the principle that the benefit of a procedure or therapy should outweigh the risk. These recent studies indicate that the accessibility and ease of testing in the past decade has eroded some of the benefit.

CT scans or CAT scanning is a non-invasive medical treatment that helps physicians diagnose and treat medical conditions. This procedure combines special x-ray equipment and computers to produce multiple images of the inside of the body. These cross-sectional images of the area are then studied on a computer monitor or printed. CT scans aid in the diagnosis of cancers, cardiovascular disease, infectious disease, trauma and musculoskeletal disorders.

A New England Journal of Medicine study concluded that one third of all CT scans (20 million a year in adults and 1 million in children) do not meet medical need criteria. Experts in the field indicate that physicians over prescribe the use of CT scans when they succumb to the pressure of their patients and the need to practice defensive medicine. Educating the public on the inherent risks of CT scans and providing physicians a safe harbor from medical malpractice by using best practice standards may keep CT scan induced cancers in check.

The CT scanner capacity worries health care reformists. The adage, “if you build it they will come‚Äù is true with expensive capital investment in medical diagnostic tools. CT scanners are expensive outlays for hospitals and clinics. Similar concerns have been directed toward MRI scanners. See my blog— MRI Capacity Leads to Unnecessary Back Surgery. The number of MRI scanners in a geographical area increased from 7.6 machines per 1 million people in 2000 to 26.6 machines per million in 2005. During the same time period the surgery rate for lower back surgery statistically increased in correlation to the increase in scan availability. The conclusion is that excess capacity increases procedures.

There are great benefits to CT scans, but they come with some risks. CT scans produce higher doses of radiation than x-rays and researchers are only now discovering that the dose is even higher than previously thought. On an individual basis the risks of a CT scan is small. If your physician ordered scan is clinically justified then the benefits of the scan far outweigh the risks. Be an informed health care consumer (use iTriageH ) and know what your options are before putting yourself at unnecessary risk.