Emergency Radiology

, Volume 20, Issue 6, pp 485–491 | Cite as

Radiation exposure among patients with the highest CT scan utilization in the emergency department

  • Kaushal H. Shah
  • Benjamin H. Slovis
  • Dan Runde
  • Brandon Godbout
  • David H. Newman
  • Jarone Lee
Original Article


The risk of cancer from computed tomography (CT) scan radiation is a rising concern in the medical field. Our objectives were to determine how many patients received more than ten CT scans in an academic emergency department (ED) over the course of 7 years and to quantify their radiation exposure and lifetime attributable risk of cancer. An electronic chart review was performed at our urban academic institution with an annual census of 110,000 patients. All patients who underwent a CT scan performed during ED management between the dates of January 2001 and December 2007 were identified. Specific predetermined data elements (e.g., subject demographics, type of CT scan) were extracted by two researchers blinded to hypothesis, using a preformatted data form. After identifying patients with more than ten CTs performed during the study period, radiation exposure was calculated based on accepted and reported radiation doses for the respective anatomic CTs, and lifetime attributable cancer risk was calculated based on the seventh report of the Biological Effects of Ionizing Radiation (BEIR VII) projections. Over the 7-year study period, 24,393 patients received 34,671 CT scans. The vast majority of patients (17,909) received a single CT. Twenty-six (0.1 %) patients received more than ten CTs totaling 374 scans with an average radiation exposure of 83.4 mSv. The maximum lifetime attributable risk for any individual in this cohort was 1.7 % above the baseline cancer risk. Among those undergoing CT imaging in our ED, high-exposure patients (greater than ten scans) constituted a significant minority, while more than one in four patients underwent more than one CT scan during the study period. While the presumed overall risk of radiation-induced cancer continues to be low, it is important for the emergency physician to use clinical knowledge as well as concern for the patient when utilizing radiographic imaging. Increasing attributable cancer risk may have important public health implications in the future, regardless of the low individual risk.


Radiation exposure Computed tomography Emergency department Lifetime attributable risk 


Conflict of Interest

The authors declare that they have no conflict of interest.


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Copyright information

© Am Soc Emergency Radiol 2013

Authors and Affiliations

  • Kaushal H. Shah
    • 1
  • Benjamin H. Slovis
    • 1
    • 5
  • Dan Runde
    • 2
  • Brandon Godbout
    • 3
  • David H. Newman
    • 1
  • Jarone Lee
    • 4
  1. 1.Department of Emergency MedicineMount Sinai Medical CenterNew YorkUSA
  2. 2.Department of Emergency MedicineHarbor UCLALos AngelesUSA
  3. 3.Department of Emergency Medicine, Lenox Hill HospitalNorth Shore LIJNew YorkUSA
  4. 4.Division of Trauma, Emergency Surgery, Surgical Critical CareHarvard Medical SchoolBostonUSA
  5. 5.New YorkUSA

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