Computed tomography utilization in South Korean Emergency Medical Centers: national trends from 2014 to 2021

Background: The global use of computed tomography (CT) scans in emergency settings is rapidly increasing; however, nationwide data from South Korean Emergency Medical Centers (EMCs) remain limited. Methods: We conducted a retrospective cross-sectional analysis using nationwide data from the National Emergency Department Information System, which collects real-time emergency medical information from EMCs across South Korea. Approximately 11 million emergency department (ED) visits involving CT scans at EMCs between 2014 and 2021 were analyzed to evaluate annual trends in CT utilization, as well as trends by EMC level, age group, Korean Triage and Acuity Scale (KTAS), CT scan region, and scan type. Results: From 2014 to 2021, the total number of CT scans performed at EMCs increased by 96.97%. The proportion of ED visits involving CT scans (CT utilization proportion) increased from 10.23% in 2014 to 25.67% in 2021 (p < 0.001). Subgroups with high CT utilization included patients aged ≥80 years, Level I EMC patients, and KTAS Level I cases. The largest increases were observed in patients aged ≥80 years (160.34%), Level III EMCs (246.61%), and KTAS Level I cases (98.59%). Among patients aged ≤9 years, CT utilization increased by 133.42%. The most common CT scan types were non-contrast brain CT, contrast-enhanced abdominal CT, and non-contrast chest CT, with non-contrast chest CT increasing sharply after 2020. Discrepancies between scanned regions and presenting symptoms have also increased, particularly in chest and abdominal CT scans. Conclusions: CT utilization has substantially increased in South Korean EMCs, particularly among subgroups with high-utilization and those vulnerable to radiation exposure. Medical and ethical considerations regarding unnecessary radiation exposure and potential low-value diagnostic imaging (LVDI) should be carefully evaluated. We propose that continuous monitoring and systematic evaluation are essential to ensure appropriate imaging practices and minimize unnecessary radiation exposure.

Computed tomography; Emergency medical centers; Diagnostic imaging; Healthcare utilization; Radiation exposure

[1] Maninchedda M, Proia AS, Bianco L, Aromatario M, Orsi GB, Napoli C. Main features and control strategies to reduce overcrowding in emergency departments: a systematic review of the literature. Risk Management and Healthcare Policy. 2023; 16: 255–266.

[2] Haas R, Brundisini F, Barbara A, Darvesh N, Ritchie L, MacDougall D, et al. Emergency department overcrowding: an environmental scan of contributing factors and a summary of systematic review evidence on interventions. Canadian Journal of Health Technologies. 2023; 3: 1–66.

[3] Pandharipande PV, Reisner AT, Binder WD, Zaheer A, Gunn ML, Linnau KF, et al. CT in the emergency department: a real-time study of changes in physician decision making. Radiology. 2016; 278: 812–821.

[4] Berdahl CT, Vermeulen MJ, Larson DB, Schull MJ. Emergency department computed tomography utilization in the United States and Canada. Annals of Emergency Medicine. 2013; 62: 486–494.e3.

[5] Ong MY, Koh JJH, Kothan S, Lai C. The incidence and associated risk factors of contrast-induced nephropathy after contrast-enhanced computed tomography in the emergency setting: a systematic review. Life. 2022; 12: 826.

[6] Hendee WR, Becker GJ, Borgstede JP, Bosma J, Casarella WJ, Erickson BA, et al. Addressing overutilization in medical imaging. Radiology. 2010; 257: 240–245.

[7] Brenner DJ, Hall EJ. Computed tomography—an increasing source of radiation exposure. The New England Journal of Medicine. 2007; 357: 2277–2284.

[8] Dunne CL, Elzinga JL, Vorobeichik A, Sudershan S, Keto-Lambert D, Lang E, et al. A systematic review of interventions to reduce computed tomography usage in the emergency department. Annals of Emergency Medicine. 2022; 80: 548–560.

[9] Levin DC, Rao VM, Parker L. The recent downturn in utilization of CT: the start of a new trend? Journal of the American College of Radiology. 2012; 9: 795–798.

[10] ElHabr A, Merdan S, Ayer T, Prater A, Hanna TN, Horný M, et al. Increasing utilization of emergency department neuroimaging from 2007 through 2017. American Journal of Roentgenology. 2022; 218: 165–173.

[11] Poyiadji N, Beauchamp III N, Myers DT, Krupp S, Griffith B. Diagnostic imaging utilization in the emergency department: recent trends in volume and radiology work relative value units. Journal of the American College of Radiology. 2023; 20: 1207–1214.

[12] Sharperson C, Hanna TN, Herr KD, Zygmont ME, Gerard RL, Johnson JO. The effect of COVID-19 on emergency department imaging: what can we learn? Emergency Radiology. 2021; 28: 339–347.

[13] Kempter F, Heye T, Vosshenrich J, Ceresa B, Jäschke D. Trends in CT examination utilization in the emergency department during and after the COVID-19 pandemic. BMC Medical Imaging. 2024; 24: 283.

[14] Arıkan C, Bora ES, Kanter E, Karaarslan FN. Have chest imaging habits changed in the emergency department after the pandemic? Tomography. 2023; 9: 2079–2088.

[15] Shi H, Han X, Jiang N, Cao Y, Alwalid O, Gu J, et al. Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study. The Lancet Infectious Diseases. 2020; 20: 425–434.

[16] Majrashi NA, Alhulaibi RA, Nammazi IH, Alqasi MH, Alyami AS, Ageeli WA, et al. A systematic review of the relationship between chest CT severity score and laboratory findings and clinical parameters in COVID-19 pneumonia. Diagnostics. 2023; 13: 2223.

[17] Samaras N, Chevalley T, Samaras D, Gold G. Older patients in the emergency department: a review. Annals of Emergency Medicine. 2010; 56: 261–269.

[18] Smith-Bindman R, Kwan ML, Marlow EC, Theis MK, Bolch W, Cheng SY, et al. Trends in use of medical imaging in US health care systems and in Ontario, Canada, 2000–2016. JAMA. 2019; 322: 843–856.

[19] Park JE, Kim Y, Lee SW, Shim SS, Lee JK, Lee JH. The usefulness of low-dose CT scan in elderly patients with suspected acute lower respiratory infection in the emergency room. The British Journal of Radiology. 2016; 89: 20150654.

[20] Gardner CS, Jaffe TA, Nelson RC. Impact of CT in elderly patients presenting to the emergency department with acute abdominal pain. Abdominal Imaging. 2015; 40: 2877–2882.

[21] Kjelle E, Andersen ER, Krokeide AM, Soril LJ, van Bodegom-Vos L, Clement FM, et al. Characterizing and quantifying low-value diagnostic imaging internationally: a scoping review. BMC Medical Imaging. 2022; 22: 73.

[22] Kjelle E, Brandsæter IØ, Andersen ER, Hofmann BM. Cost of low-value imaging worldwide: a systematic review. Applied Health Economics and Health Policy. 2024; 22: 485–501.

[23] Kim HJ, Jeon BG, Hong CK, Kwon KW, Han SB, Paik S, et al. Low-dose CT for the diagnosis of appendicitis in adolescents and young adults (LOCAT): a pragmatic, multicentre, randomised controlled non-inferiority trial. The Lancet Gastroenterology & Hepatology. 2017; 2: 793–804.

[24] Yi DY, Lee KH, Park SB, Kim JT, Lee NM, Kim H, et al. Accuracy of low dose CT in the diagnosis of appendicitis in childhood and comparison with USG and standard dose CT. Jornal de Pediatria. 2017; 93: 625–631.

[25] Kim MC, Chang KH, Hwang JH, Nam YC, Han DK, Yoon J. Radiation dose for pediatric and young adult CT: a survey to establish age-based reference levels of 2015–2016 in Korea. Radiation Protection Dosimetry. 2017; 175: 228–237.

[26] Cohen E, Rodean J, Diong C, Hall M, Freedman SB, Aronson PL, et al. Low-value diagnostic imaging use in the pediatric emergency department in the United States and Canada. JAMA Pediatrics. 2019; 173: e191439.

[27] Marin JR, Hollander MA, Ray KN, Donohue JM, Cole ES. Low-value diagnostic imaging in children with Medicaid. The Journal of Pediatrics. 2021; 235: 253–263.e14.

[28] Colla CH, Mainor AJ. Choosing Wisely campaign: valuable for providers who knew about it, but awareness remained constant, 2014–17. Health Affairs. 2017; 36: 2005–2011.

[29] Hiscock H, Neely RJ, Warren H, Soon J, Georgiou A. Reducing unnecessary imaging and pathology tests: a systematic review. Pediatrics. 2018; 141: e20172862.

[30] Russell WS, Schuh AM, Hill JG, Hebra A, Cina RA, Smith CD, et al. Clinical practice guidelines for pediatric appendicitis evaluation can decrease computed tomography utilization while maintaining diagnostic accuracy. Pediatric Emergency Care. 2013; 29: 568–573.

[31] Oh HY, Kim EY, Cho J, Yang HJ, Kim JH, Kim HS, et al. Trends of CT use in the adult emergency department in a tertiary academic hospital of Korea during 2001–2010. Korean Journal of Radiology. 2012; 13: 536–540.

[32] Iacobellis F, Abu-Omar A, Crivelli P, Galluzzo M, Danzi R, Trinci M, et al. Current standards for and clinical impact of emergency radiology in major trauma. International Journal of Environmental Research and Public Health. 2022; 19: 539.

[33] Salastekar NV, Duszak R, Santavicca S, Horný M, Balthazar P, Khaja A, et al. Utilization of chest and abdominopelvic CT for traumatic injury from 2011 to 2018: evaluation using a national commercial database. American Journal of Roentgenology. 2023; 220: 265–271.

[34] Bunn C, Ringhouse B, Patel P, Baker M, Gonzalez R, Abdelsattar ZM, et al. Trends in utilization of whole-body computed tomography in blunt trauma after MVC: analysis of the Trauma Quality Improvement Program database. Journal of Trauma and Acute Care Surgery. 2021; 90: 951–958.

[35] Moussavi N, Ghani H, Davoodabadi A, Atoof F, Moravveji A, Saidfar S, et al. Routine versus selective chest and abdominopelvic CT-scan in conscious blunt trauma patients: a randomized controlled study. European Journal of Trauma and Emergency Surgery. 2018; 44: 9–14.