Despite a general slowdown in imaging utilization overall, the rates of emergency department imaging continue to increase across the country, according to a recent study in the Journal of the American College of Radiology.

David C. Levin, MD, of Thomas Jefferson University in Philadelphia, and colleagues looked at imaging rates using the Medicare Part B Physician/Supplier Procedure Summary Master Files during a 10-year span (2002-2012) as a data source. This database shows annual data by procedure code and includes examination volume, location of the examination and specialty of the physician.

What the researchers found was an increasing trend in the utilization rate per 1,000 Medicare beneficiaries of x-ray in emergency departments. The rate of utilization increased steadily and progressively from 248.7 per 1,000 in 2002 to 320 per 1,000 in 2012, an increase of 29 percent.

For CT scans, use grew rapidly every year except 2011, when a decrease was shown due to bundling CPT codes for scanning of the abdomen and pelvis. During the entire study period, the rates of CT scans in emergency departments grew from 57.2 in 2001 to 147.9 in 2012, an increase of 159 percent.

Both MRI and nuclear medicine were graphed together in the study because their numbers were so similar, and both are used far less in emergency departments than x-ray and CT scans. In nuclear medicine, there was in increase between 2002 and 2009 before a drop occurred in 2010, also caused by code bundling. Nuclear medicine went from 2.8 in 2002 to 2.1 in 2012 (a 25 percent decrease) due to code bundling. Rates for MRI in emergency departments increased by 264 percent—1.4 in 2002 to 5.1 in 2012.

In contrast, the researchers found use of all three major imaging modalities decreased outside of the emergency department. The non-emergency department use of x-ray per 1,000 Medicare patients was 1,805.9 in 2002 and was 1,673.3 in 2012. Rates for CT were 346.9 in 2002 then rose to as high as 494.1 in 2008 before finally dropping to 350.0 in 2012.

“Utilization rates of imaging in [emergency departments] are clearly continuing to increase in the Medicare population,” researchers wrote. “This is in contrast to the overall trends seen when all other places of service are considered.”

The team found that in 2012, a total of more than 18 million imaging studies were performed in emergency departments, constituting 14 percent of all Medicare fee-for-service imaging.

“At a time when others in health care are expecting radiologists to play a larger role in managing the utilization of their technology, it is of concern that [emergency department] imaging rates continue to grow,” Levin and colleagues wrote.

The researchers suggest radiologists work more closely with emergency physicians to reduce the ordering of imaging examinations if they aren’t absolutely necessary. The authors suggested mechanisms like more diligent rules for imaging, more education for emergency department physicians about imaging appropriateness, cooperation between radiologists and emergency department physicians, use of computerized clinical decision support and greater familiarity among both radiologists and emergency physicians with the list of overused and unnecessary imaging tests.