Between 1998 and 2007 there was a huge rise in medical imaging scan usage in emergency departments of hospitals in the USA, but without a comparable rise in diagnoses of life-threatening conditions or illnesses, experts report in an article published in the Journal of the American Medical Association (JAMA). Examples of imaging scans include MRI (magnetic resonance imaging) and CT (computerized tomography)
The researchers, from Johns Hopkins Medicine in Baltimore, USA, reviewed a decade’s worth of nationally collected ER (emergency department) data from 1998 through 2007.
The authors report that a patient in 2007 had a three-times higher chance of undergoing a CT or MRI scan in 2007 compared to 1998 if he/she had an injury-related condition. However, there was only a modest rise in the number of diagnoses of life-threatening conditions, such as liver lacerations or cervical spine fractures over the same ten-year period.
The proportion of patients seen in emergency departments who were then hospitalized remained virtually the same during that period, the researchers add.
In short – from 1998 through 2007:
- imaging scans tripled
- diagnoses of life-threatening conditions rose slightly
- the percentage of emergency department patients who ended up being hospitalized remained the same
The investigators said that studying this trend is not only significant for a cost-benefit reason, but also because medical imaging subjects patients to more radiation exposure.
If many more patients are being exposed to radiation, especially via multiple CT scans, but the number being treated for life-threatening injuries has not risen proportionately, one has to wonder whether the increased risk is still outweighed by the benefits.
The authors write:
The carcinogenic effects of exposure to CT are especially important in patients presenting with injury-related conditions because they tend to be younger and receive multiple CTs.
The researchers added:
(there is an) increased length of visit in the emergency departments due to the long waiting period for imaging results. This can contribute to emergency department crowding and can increase the risk of medical error.
According to the investigators, there are several reasons for the increase in the number of imaging scans in US emergency departments.
The authors write:
Some factors that may have contributed to this significant increase in CT use are the superiority of CT scans over x-rays for diagnosing conditions such as cervical spine fractures, the routine use of whole-body scanning for patients treated in some trauma centers, the increased availability of CT scanners, the proximity of CT scanners to the patient care areas of most emergency departments, the speed of new-generation CT scanners leading to a decrease in the need to sedate pediatric patients, and concern about malpractice lawsuits for a missed diagnosis.
More studies are required, the investigators believe, to better understand why this is happening, and to provide guidance to doctors on how to proceed.
Frederick Kofi Korley, MD; Julius Cuong Pham, MD, PhD; Thomas Dean Kirsch, MD, MPH
JAMA. 2010;304(13):1465-1471. doi:10.1001/jama.2010.1408
Written by Christian Nordqvist