Project tallies lifetime radiation from health scans

Intermountain Healthcare in Salt Lake City is at the forefront of a relatively new movement in medicine to measure patients' cumulative medical radiation exposure and document it in electronic health records.

The goal is to alert physicians to patients who have received multiple high-dose imaging procedures, such as angiography and computed tomography screens, and encourage doctors to consider nonradiation alternatives to testing when possible. Alternatives could include magnetic resonance imaging or ultrasound, medical experts say.

“Anybody that denies [medical] radiation matters [to patients' health] is not being honest,” said Donald L. Lappé, MD, medical director of Intermountain Healthcare's cardiovascular clinical program.

“We're not saying necessary tests shouldn't be done. But only do the procedures that need to be done,” said Dr. Lappé, who helped develop and implement the Utah program in 2012.

Some medical experts are divided on the benefits of tracking and reporting patients' cumulative radiation exposure, but most agree that physicians should be aware of how many imaging tests their patients have received.

The push to track the total millisieverts of radiation patients are exposed to in medical imaging was ignited by a flurry of studies in the past 10 years, radiology experts said.

Many of those reports show that patients who receive CT scans have an increased risk of developing cancer later in life than individuals who never had such a screen. For example, an estimated 4 million pediatric CT scans of the head, abdomen/pelvis, chest or spine are performed each year in the U.S., and they are projected to cause about 4,870 future cancers, said a study posted online June 10 in JAMA Pediatrics, formerly Archives of Pediatric and Adolescent Medicine.

Increasing the urgency to address the issue was a surge in the use of medical imaging in the past two decades, medical experts said.

Between 1980 and 2006, the annual number of CT scans performed in the U.S. grew from 3 million to 60 million, according to a report by IMV, a market research company in Greenbelt, Md., though physicians say use of the screening is beginning to decrease.

Some proponents of measuring and documenting cumulative medical radiation say it leads to a reduction in unnecessary imaging tests, because doctors can see how much radiation patients are exposed to and ultimately decreases patients' cancer risk.

Some radiology experts worry, however, that tracking cumulative radiation is dangerous, in part because its link to an increased cancer risk still is just an estimate, and there is no clear indication of what constitutes a safe cumulative dose of medical radiation for children or adults.

“The question for health care professionals is what do they do with the [cumulative radiation] numbers?” said James A. Brink, MD, radiologist-in-chief at Massachusetts General Hospital in Boston.

For now, the answer is no one knows, said Dr. Brink, chair of the Commission on Body Imaging for the American College of Radiology.

Some physicians worry that patients' access to their cumulative radiation numbers could increase liability risks for doctors if individuals received multiple imaging tests and later developed cancer. Patients could blame physicians who ordered the screens for their cancer, some say.

Another concern is that cumulative numbers that seem elevated could lead patients to refuse necessary imaging tests and keep physicians from ordering them.

“Imaging has revolutionized medicine, and I don't want people to become afraid of it,” said New York radiologist E. Stephen Amis Jr., MD. “Not doctors or patients.”

Hospital tracks tests

At Montefiore Medical Center, where Dr. Amis works, the number of CT scans patients receive has been tracked since 1997. The medical center does not, however, record patients' cumulative radiation exposure.

When a physician orders a CT for patients, an alert will appear in the EHR if the individual has received five or more such scans at Montefiore, said Dr. Amis, university chair in the Dept. of Radiology at Montefiore Medical Center and Albert Einstein College of Medicine in New York.

Five scans would expose people to an estimated total of 50 millisieverts of radiation, Dr. Amis said. That was set as the threshold because data on survivors of the atomic bombs that the U.S. dropped on Hiroshima and Nagasaki in Japan in 1945 showed a significant increase in cancer risk among people exposed to 50 to 100 millisieverts of radiation.

“The goal is simply to get the ordering physician to say, 'Oh, gee. I didn't realize my patient had five or 10 CTs over the past 15 years. Maybe I should think about doing something different than a CT scan,' ” Dr. Amis said.

Intermountain Healthcare takes it a step further by documenting the number of millisieverts of radiation patients receive from four relatively high-dose procedures: angiography, cardiac catheterization procedures, CT scans and nuclear cardiology. The information is available to physicians and patients on the health care center's secure website.

Dr. Lappé said this is an affordable system for facilities to implement, because the key feature, which is documenting the amount of radiology uses by imaging tests, doesn't cost anything.

Since tracking began in 2012, his patients increasingly have asked him about low-radiation tests when a screening procedure is needed. He hasn't, however, heard of any patients refusing imaging tests.

There is some concern about increased liability now that patients can access their cumulative radiation exposure, Dr. Lappé said. But he added, “Most of us believe that if you provide evidence-based care and appropriate decision-making, you can stand up tall for what you've done.”

Program raises patient awareness

Efforts are being made at federal and state levels to decrease patients' medical exposure to radiology.

In 2010, the Food and Drug Administration launched an initiative to reduce unnecessary radiation exposure by promoting safe use of medical imaging devices, supporting informed clinical decision-making on imaging tests and increasing patient awareness about radiation exposure.

That year, the California Legislature enacted a law requiring all medical facilities to record the radiation exposure from every CT study and report it to physicians and patients. The law went into effect in July 2012.

The Environmental Protection Agency is updating its radiation protection guidance for diagnostic and interventional x-ray procedures for federal facilities. The report's objective is to keep radiation doses to patients as low as possible without compromising quality of care. Once approved, it will replace guidance that was issued in October 1976, the EPA said.

The American Medical Association said in a June 3 letter to the EPA that the limited number of physicians who helped develop the guidance leads to the appearance that the report lacks objectivity and balance. The AMA disagreed with the report's assertion that exams performed or interpreted by nonradiologists frequently are performed by equipment or operators lacking adequate training.

The AMA urged the EPA to engage more directly with the medical community as it moves forward.