When most people think of the Food and Drug Administration (FDA), they think food, drugs, and possibly medical devices, but FDA's Center for Devices and Radiological Health (CDRH) is also responsible for consumer, industrial, and medical products that emit electromagnetic radiation, from radio waves to microwaves to light and sound, as well as X-rays. In the early years, the FDA relied solely on mandatory standards to address manufacturing and equipment problems. There are now effective national and international consensus standards in addition to the mandatory standards. In part, due to these standards, the design and manufacturing of electronic products is less of a problem. Over time, excessive radiation from items such as televisions and microwave ovens has become a thing of the past. At the same time, medical X-ray equipment can emit more intense radiation for longer periods of time, and is being used by more practitioners on more patients for more types of procedures than ever before. Meanwhile, the FDA has faced declining financial and staff resources. The once 400-strong staff of the radiological health group dropped to about 90, with about 40 of those individuals dedicated to implementing the Mammography Quality Standards Act.

As both the world at large and the financial landscape changed, CDRH needed to focus its efforts and resources in an area where the risk was greatest and where the greatest gains in public health and safety could be achieved. One of the areas that fits this paradigm is medical X-ray, especially for dose-intensive procedures such as CT and fluoroscopy, where preventable cancer deaths from population radiation burden and injuries such as burns result when exposures are unnecessary or unnecessarily high. For example, in 2001, Brenner et al. [1] estimated that the number of CT examinations done in this country in one year could result in 2,500 deaths from cancer in the future.

In an effort to reduce dose, CDRH partners with the international CT community by actively participating in the International Electrotechnical Commission (IEC) standards development committees to ensure that equipment is designed and built to maximize the diagnostic information while allowing the control and reduction of unnecessary radiation dose. While equipment improvements and features such as more sensitive image intensifiers, last image hold, and digital systems in general can result in reduced patient dose, care in delivering dose must be taken, as some of the old “safeguards” to alert radiologists to high doses, such as film overexposure, are absent.

The CDRH's new radiation health focus is to promote the mantra: every time a patient is exposed to medical X-ray that it be (as the American College of Radiology [ACR] has so clearly stated), “the right exam, for the right reason, at the right time.” The techniques should be optimized to minimize the dose to that necessary to get the job done. So, what can radiologists do to achieve this goal? First, ensure that the exam is the right one to obtain the information needed. This can be achieved by developing and using exam-appropriateness criteria such as the ACR criteria, both for screening patients for exams as well as for educating referring providers about what exam is appropriate for what circumstance. In some cases, it may be more appropriate to use a nonionizing type of exam such as sonography or MRI, thus avoiding the risks of ionizing radiation. Second, adjusting techniques and protocols should not be dependent only on patient age and body size, but also on the clinical image quality necessary for the condition being evaluated. CDRH encourages partnerships with professional organizations that have made substantial contributions to dose reduction, including the American Roentgen Ray Society, the ACR, the Radiological Society of North America, the Society for Pediatric Radiology, and the American Association of Physicists in Medicine. By eliminating unnecessary exams and eliminating unnecessary exposure in the exams that need to be done, patients will get the benefit of the exam while reducing patient and population medical X-ray exposure and the risk of future cancer deaths.

Third, in their own institutions radiologists can help educate nonradiologist colleagues who use X-rays about ways to reduce dose and injuries. CDRH worked on an outreach plan with the American College of Cardiologists on steps to reduce dose, and placed information on the CDRH Web site about whole-body CT scanning and pediatric CT, which can be viewed at http://www.fda.gov/cdrh/ct/index.html. In addition to providing information to health professionals and consumers, CDRH is at work on the regulatory front in radiation health. It recently published an amendment to the X-ray standard for fluoroscopy systems, available at http://www.fda.gov.radhlth/xraystandard.html. The amended standard requires manufacturers to provide a display for the operator that indicates exposure rate and the cumulative exposure to the patient. This information will allow users to take steps to reduce patient exposure. Cumulative exposure information can be recorded in patient charts for future reference for that particular patient and in a facility database as a way of collecting dose data in a systematic manner for quality control by the facility.

Another area in which CDRH is actively involved is in efforts to reduce population X-ray exposure in personnel security screening. Since 9/11, there has been a significant rise in the use of X-ray “people scanning” systems at venues such as workplaces and sporting and entertainment events. In response, CDRH, along with the American National Standards Institute/Health Physics Society helped develop a standard, N43.17-2002, Radiation Safety for Personnel Security Screening Systems Using X-Rays.

CDRH is also updating the way it deals with public exposure to nonionizing electromagnetic radiation exposure. While making requirements easier for the manufacturers of low-risk laser products such as CD players, CDRH is also working with other federal agencies to address the issue of the misuse of high-powered laser pointers. CDRH is also involved in an important outreach campaign to make school officials and consumers aware that injuries such as skin burns and eye irritation from ultaviolet exposure from broken mercury lamps, such as those used in gyms, can be avoided by using self-extinguishing lamps. The safety issues are outlined in an article on the FDA and You site, FDA's Web page providing information for educators and students, which can be viewed at http://www.fda.gov/cdrh/fdaandyou/issue08.pdf.

In order to involve the entire interested community in its radiation health initiatives, CDRH held a stakeholders' meeting on October 31 and November 1, 2005. Participants included representatives from industry and industry associations, health care professionals and their organizations, radiation health professionals from a number of states, and national and international standards organizations. All the major radiology societies participated. Outcomes of this gathering included suggested educational initiatives, collaborations to achieve more efficient regulations, and sharing of information in an effort to monitor the high-risk procedures. Specifics about the meeting and any meetings scheduled for the future can be found at http://www.fda.gov/cdrh/radhlth/initiative.html.

By focusing its available resources on encouraging users who perform dose-intensive medical X-ray procedures to be aware of radiation exposures and to use techniques and protocols to reduce dose, by requiring dose displays on fluoroscopy equipment, by developing standards for nonmedical X-ray exposure, by providing information to health care professionals and consumers, and by partnering with interested stakeholders, the FDA will continue its vital role in promoting and protecting the public health in the radiation health arena. More information on FDA's radiation health program can be found at http://www.fda.gov/cdrh/radhealth.html.