New FDA Initiative to Reduce Unnecessary Radiation Exposure From Medical Imaging

From Medscape Medical News
Robert Lowes

February 10, 2010 — In a move that promises more regulation for imaging device manufacturers and imaging facilities, the US Food and Drug Administration (FDA) yesterday announced it was launching a campaign to reduce unnecessary radiation exposure from 3 types of procedures — computed tomography (CT), nuclear medicine studies, and fluoroscopy.

The FDA said it would work to promote the safe use of these 3 modalities, help physicians make more informed decisions about ordering tests, and increase patient awareness of their individual radiation exposure.

CT, nuclear medicine studies, and fluoroscopy subject patients to ionizing radiation that can increase their lifetime cancer risk, according to the FDA. In addition, accidental exposure to very high amounts of radiation can cause skin burns, hair loss, and cataracts.

"The amount of radiation Americans are exposed to from medical imaging has dramatically increased over the past 20 years," Jeffrey Shuren, MD, JD, director of the FDA's Center for Devices and Radiological Health, said in a news release. "The goal of FDA's initiative is to support the benefits associated with medical imaging while minimizing the risks."

The agency cites a March 2009 report from the National Council on Radiation Protection and Measurements showing that nationwide exposure to ionizing radiation has nearly doubled during the past 2 decades, with the increase largely attributable to CT, nuclear medicine studies, and fluoroscopy. According to the FDA, the 3 modalities account for 26% of imaging procedures involving radiation but contribute 89% of the annual exposure that patients have from medical imaging.

The new FDA campaign follows on the heels of an investigation last year into roughly 250 patients at Cedars-Sinai Medical Center in Los Angeles, California, who were exposed to excessive levels of radiation during CT perfusion scans of their brains.

Building Smarter Imaging Devices

The FDA plans to attack the problem of excessive radiation exposure with a 3-pronged approach. The first prong involves the safe use of imaging devices. The agency said Tuesday that it would issue requirements for makers of CT and fluoroscopic equipment to provide safety training for clinicians as well as include safeguards in the design of the devices. Such safeguards might be the ability to display, record, and report equipment settings and radiation doses; alert users when a dose exceeds a diagnostic reference level; and transmit dose data to a patient's electronic health record or dose registry. The FDA plans to hold a public meeting on March 30 and March 31 to solicit ideas about what these requirements should be.

The FDA also plans to work with the Centers for Medicare and Medicaid Services to incorporate quality-assurance practices for medical imaging in the Centers for Medicare and Medicaid Services accreditation of stand-alone imaging facilities, as well as its conditions of participation for hospitals in the Medicare program.

Another component of safer medical imaging is nationally recognized diagnostic radiation reference levels for imaging procedures so that clinicians can assess whether a radiation dose is reasonable. The FDA said it would help promote the development of local and national radiation dose registries to achieve this end.

Helping Physicians and Patients Make Wiser Choices

Because physicians are responsible for ordering diagnostic imaging procedures, the FDA said it wants to support informed clinical decision-making as part of its initiative. Proposed "smart" features such as alerts built into imaging devices are part of that thrust. At the same time, the FDA is recommending that physicians develop and adopt "appropriate use criteria" for ordering CT, fluoroscopy, and nuclear medicine studies. Physicians may order these procedures without sufficient justification — and expose patients unnecessarily to radiation — because they are unaware of recommended clinical criteria to guide their decisions, according to an FDA white paper.

The third prong of the FDA initiative is increasing individual patients' awareness of their exposure to radiation from medical imaging. The FDA said it would collaborate with other organizations, such as the American College of Radiology and the Radiological Society of North America, to develop and distribute a patient "medical imaging card" to help individuals track their procedures and share that information with clinicians.