Overuse of CT Scans Lead to Radiation Exposure Problems, Experts Say

Two articles posted this week in a prominent medical journal question the wisdom of the growing reliance on computed tomography (CT) scans following increasing concerns about radiation exposure. 

The articles were published in this week’s New England Journal of Medicine by Dr. Rebecca Smith-Bindman, a radiologist performing radiation research at the National Cancer Institute, and by Dr. Bruce J. Hillman of the University of Virginia and Jeff Goldsmith, president of Health Futures Inc. Both of the articles questioned the overuse of CT scans and recommended that the medical community do what it could to ensure that CT scans and other imaging methods were both necessary and safe.

In her article, “Is Computed Tomography Safe?” Dr. Smith-Bindmen points out that CT scans expose patients to 100 to 500 times more radiation than other types of x-ray scans. Yet, she points out that there is no professional or governmental organization responsible for collecting, monitoring or reporting CT Scan dose information.

“Studies have shown that physicians know little about radiation doses or cancer risks from medical imaging,” Dr. Smith-Bindmen writes. “CT technologists receive no consistent education about what doses are excessive and, in many U.S. states, are not certified.”

CT scan procedures and other forms of radiation therapy across the country are under close scrutiny by the FDA after the discovery that a number of patients have suffered radiation overexposure from CT Scans performed incorrectly. The FDA is currently reviewing CT scan and radiation therapy procedures nationwide, and released interim guidance for health care professionals and radiologists in December. The guidance advised them to review procedures and CT scan settings, and to be thorough in checking the amount of dosage prescribed for each CT scan patient.

Smith-Bindmen recommended that the medical community move to lower doses for CT scans, pointing out that studies have shown that radiation from the scans could be reduced by 50% without a reduction in diagnostic accuracy. She suggested a profession-wide standardization of CT protocols and techniques with established radiation levels with safety having a higher priority than producing better quality scan images.

Dr. Hillman and Goldsmith also pointed to education and lack of standards as a problem in CT scan radiation exposure in their article, “The Uncritical Use of High-Tech Medical Imaging,” suggesting that the root cause of unnecessary use of imaging could be clinical education.

“All new physicians are educated, and the majority trained, in academic medical centers, where the acuteness and complexity of illness tend to be high,” they wrote. They suggest that students and faculty are under high stress dealing with both clinical care and scholarly activities, and focus on efficiency and develop habits that stay with them throughout their medical careers, taking their “high-intensity practice patterns” into the medical field wherever they go, where illness and probability of disease are in a more moderate range.

While mentioning both tort reforms and putting restrictions on physicians who refer patients to their own imaging labs, Hillman and Goldsmith said that ultimately, changes should probably start at medical school, teaching a different CT scanning mindset.

The recent FDA investigation was sparked by the discovery of CT scan radiation over-exposure problems that may have affected more than 200 patients at Cedars-Sinai Medical Center in Los Angeles last year. Since then, the FDA has uncovered at least 50 more radiation CT errors.

The FDA has said that it received more than 1,200 complaints since 2000 from patients who received radiation therapy, and urged the industry to add new radiation safeguards.

A number of errors discovered by FDA have involved massive doses of radiation being directed at the wrong parts of the body, and machines being set incorrectly, resulting in overly large radiation doses.

Earlier this month, radiation therapy equipment manufacturers released new industry guidelines aimed at reducing radiation exposure mistakes.