It is well recognized that computed tomography (CT) imaging has become a cornerstone of diagnostic evaluation in emergency medicine, particularly for complex presentations such as trauma, cerebrovascular accidents, intracranial injuries, and abdominal pain.¹ However, the increasing reliance on CT has raised important ethical considerations related to the principle of non-maleficence, given concerns about excessive radiation exposure.^2-4 A recent JAMA Internal Medicine study by Smith-Bindman et al.⁵ adds valuable data to this ongoing discussion.

Using CT imaging data from 2018 to 2020, Smith-Bindman and colleagues performed an analysis of patient demographics, scanned body regions, and diagnostic indications to estimate radiation doses per scan. They subsequently developed a model projecting the number of cancers potentially induced by CT radiation exposure. Based on 93 million CT scans performed in the United States in 2023, their model estimated approximately 103,000 new cancers attributable to CT imaging, roughly 5 percent of all annual cancer diagnoses.⁵

The authors further stratified their projections by body region, cancer type, sex, and age group, including pediatric patients. While acknowledging limitations, such as reliance on risk estimates derived from atomic bomb survivor data and potential overestimation in populations with reduced life expectancy, the study nevertheless highlights a critical issue warranting broader reflection.

Although clinicians are generally aware that plain radiographs (X-rays) expose patients to ionizing radiation, they may not be aware that the magnitude of exposure from CT is far greater: The average effective dose for a chest X-ray is 0.1 mSv compared with 7 mSv for a chest CT.⁶ For context, the average American receives approximately 6.2 mSv annually from background radiation.⁷ These are facts of which some clinicians may not be aware.⁸ This further emphasizes the significance of Smith-Bindman et al.’s retrospective modeling study, as it enables imperative reflection on current clinical practices.

The study’s projections are particularly relevant to emergency medicine, where CT utilization continues to rise. A 2019 survey of over 1,000 U.S. emergency departments reported CT use in 27 per 100 patient encounters, nearly equivalent to the use of electrocardiography (28 per 100 patients).⁹ With CT rates steadily increasing over time,^1,9 and approximately 19 percent of ED visits leading to inpatient admission, where additional imaging may occur,^10,11 emergency clinicians should view these findings as a call for vigilance.

Another factor to consider is that certain populations have historically relied more heavily upon EDs due to financial and other barriers preventing their access to primary care.^12-14 This may disproportionately expose these groups to excessive radiation, further exacerbating existing health disparities.

To mitigate the risks associated with CT radiation, emergency physicians must balance the benefits of rapid imaging with judicious clinical judgment. The current trend toward increased imaging driven by clinical scoring systems,¹⁵ artificial intelligence–assisted decision tools,¹⁶ and workflow pressures should not supplant fundamental diagnostic skills. A thorough history and physical examination,¹⁷ coupled with careful clinical reasoning, remain essential safeguards against overreliance on imaging. When appropriate, alternative modalities such as X-ray^18,19 or ultrasonography^20-22 should be considered.

Of course, system-level factors, including staffing shortages,^23,24 fears of malpractice,²⁵ and challenges communicating diagnostic uncertainty²⁶ contribute to the pervasive use of CT in emergency care.^1,27,28 Nonetheless, the increasing availability of diagnostic technologies must not replace sound clinical judgment. Both clinicians and artificial intelligence systems are prone to bias and error,^16,29 reinforcing the need for thoughtful application rather than indiscriminate use.

Efforts to reduce unnecessary CT imaging in the ED have been underway for years,^30,31 and continued progress depends on clinician engagement. First, greater discretion should be exercised when ordering abdominopelvic CT scans, the region most strongly associated with projected CT-induced cancers (approximately 39,100 cases).⁵ Second, clinicians should rely on other diagnostic tools such as ultrasonography, X-ray, MRI, or laboratory studies when feasible.^18-22,32-34 Third, consideration of alternatives such as observation with serial examinations, expert consultation with specialists, and focused differential diagnoses to minimize radiation exposure to unnecessary body regions must be done.

At a system level, greater transparency with radiation risk when ordering scans,³⁵ dashboards displaying a practitioner’s imaging usage,³⁶ and increasing radiation science education at the undergraduate and graduate medical education level should be considered.^35-37 Reinforcing these strategies and revisiting prior initiatives to curtail avoidable imaging^31,38 can help reduce ionizing radiation exposure, limit radiation-related cancer risk, and uphold our commitment to both the immediate and long-term well-being of patients.

Chinonso A. Nwakama, BS, is a third-year MD-PhD student at the Icahn School of Medicine at Mount Sinai. He studiedNeuroscience and History at the University of Minnesota – Twin Cities. For his PhD, Chino is researching neurodegeneration in the context of Opioid Use Disorder in the lab of Dr. Yasmin Hurd.

Dr. Bess M. Storch , MD, is an emergency medicine physician at Mount Sinai West-Morningside Hospitals in New York City. She is the co-director of the pre-clerkship clinical skills curriculum and the evidence-based medicine curriculum at the Icahn School of Medicine at Mount Sinai.

Dr. Ugo A. Ezenkwele, MD, MPH, FACEP, is a professor of emergency medicine at the Icahn School of Medicine at Mount Sinai and system vice chair for Strategic Community Engagement and Development for the Department of Emergency Medicine, Mount Sinai Health System. A nationally recognized leader in health equity, diversity, and emergency medicine operations, he has led transformative initiatives in clinical excellence, workforce development, and community engagement, earning multiple national awards for leadership and inclusion.

Funding and support: T32GM146636 (C.A.N)

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