Over the years, medical imaging equipment such as X-rays, computed tomography (CT), and magnetic resonance imaging (MRI) have played important roles in providing quality health—by quickly and quietly detecting problems ranging from brain tumors to aneurysms. And, radiation therapy has become important in providing high-quality cancer care.
But recent studies and reports linking radiation overexposure for various reasons to cancer risks, illness, and even death may be the start of a new era in the diagnostic and therapeutic uses of radiation. How can we best reap the benefits while avoiding the risks?
Late last year, in a study published in the Archives of Internal Medicine, researchers estimated that radiation from CT scans done in 2007 could cause 29,000 cancers and kill nearly 15,000 Americans. Currently, more than 70 million CT scans (which can have 50- to 500-times the radiation dose of X-rays) are given in the U.S. today annually—up from 3 million 30 years ago.
In some instances, these scans may be related to overuse or unnecessary use. For instance, a study from this month's Journal of the American College of Radiology that found that one in four MRI and CT scans were "inappropriately recommended" by doctors. The researchers found that of 459 scans at Harborview Medical Center in Seattle, 26% were considered "inappropriate."
On the therapeutic side, emerging stories—such as those presented last week at a congressional hearing on radiation benefits and risks—indicate a need for more safeguards and more staff training as well.
One of the stories presented at the Feb. 25 House hearing was that of the late Scott Jerome Parks. His father testified that Jerome-Parks accidentally had received treatments seven times more powerful than required for his tongue cancer—causing him to go blind and deaf. He eventually died. The cause: malfunctioning computer software that had not been detected by a technician.
So can more be done to address these issues? The answer is yes, of course. But, it is going to require multiple and overlapping efforts on many fronts from both the private and public sectors.
Federal assistance: The issue of overexposure received high-profile attention last month when the federal Food and Drug Administration (FDA) issued a new initiative to reduce unnecessary radiation exposure from three types of medical imaging procedure—CT, nuclear medicine studies, and fluoroscopy.
These combined procedures are considered the leading contributors to total radiation exposure in the U.S., because they use higher radiation doses than other radiographic procedures, such as standard X-rays, dental X-rays, and mammography, according to the FDA. Of concern was exposing patients to ionizing radiation a type of radiation that can increase an individual's lifetime cancer risk.
As the first prong of the initiative, FDA said it intends to issue targeted requirements for manufacturers of CT and fluoroscopic devices. These requirements address safeguards in the design of their machines and provide appropriate training to support safe use by practitioners.
For the second part of the initiative, FDA and the Centers for Medicare and Medicaid Services will work together to incorporate key quality assurance practices into the mandatory accreditation and conditions of participation survey processes for imaging facilities and hospitals.
One size does not fit all. In an ongoing campaign, the Alliance for Radiation Safety in Pediatric Imaging has reached out on behalf of especially vulnerable populations: Young children. Prior to 2001 the majority of CT imaging for children was conducted using the same techniques—and radiation levels—used for adult imaging.
Imaging teams and members of the community are encouraged to play different roles in using the "image gently" philosophy—to ensure that CT scans for children are performed at levels that are most appropriate for them.
Professional organization assistance. Last month, one professional organization dedicated to radiation oncology called for enhancing safety measures in administering medical radiation-including establishing the nation's first central database for the reporting of errors involving linear accelerators and CT scanners.