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Variations in CT Utilization, Protocols, and Radiation Doses in COVID-19 Pneumonia: Results from 28 Countries in the
Fatemeh Homayounieh1, Ola Holmberg1, Rashid Al Umairi1
1From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 75 Blossom Ct, Room 248, Boston, MA 02114 (F.H., M.K.K.); Radiation Protection of Patients Unit, International Atomic Energy Agency, Vienna, Austria (O.H., J.V.); The Royal Hospital, Muscat, Oman (R.A.U.); Alfa Scan Radiology Center, Cairo, Egypt (S.A.); Department of Radiology, Lithuanian University of Health Sciences, Kaunas, Lithuania (A.B.); Institute of Physics, University of São Paulo, São Paulo, Brazil (P.R.C.); Hamad Medical Corporation, Doha, Qatar (A.D.); Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University, Skopje, North Macedonia (V.G.); Tartu University Hospital, University of Tartu, Institute of Clinical Medicine, Department of Radiology, Tartu, Estonia (P.I.); Aleksandrovska University Hospital, Sofia, Bulgaria (D.K.L.); Institute of Radioprotection and Dosimetry, National Nuclear Energy Commission, Rio de Janeiro, Brazil (S.K.R.); Radiology Department, Firouzgar Hospital, Iran University of Medical Sciences, Tehran, Iran (I.M.); Medical Physics Unit, A.O.U. Città della Salute e della Scienza di Torino, Turin, Italy (O.R.); Nicolae Testemitanu State University of Medicine and Pharmacy, Chisinau, Moldova (N.R.); Radiological and Medical Sciences Research Institute, Ghana Atomic Energy Commission, Accra, Ghana (I.S.); University Hospital, Lomonosov Moscow State University, Moscow, Russian Federation (V.S.); University Hospital Osijek, Faculty of Medicine, J.J. Strossmayer University of Osijek, Osijek, Croatia (T.T.); and Department of Radiology, Hôpital Européen Georges Pompidou, Paris, France (C.V.N.T.).
Abstract:
Background There is lack of guidance on specific CT protocols for imaging patients with coronavirus disease 2019 (COVID-19) pneumonia. Purpose To assess international variations in CT utilization, protocols, and radiation doses in patients with COVID-19 pneumonia. Materials and Methods In this retrospective data collection study, the International Atomic Energy Agency coordinated a survey between May and July 2020 regarding CT utilization, protocols, and radiation doses from 62 health care sites in 34 countries across five continents for CT examinations performed in patients with COVID-19 pneumonia. The questionnaire obtained information on local prevalence, method of diagnosis, most frequent imaging, indications for CT, and specific policies on use of CT in COVID-19 pneumonia. Collected data included general information (patient age, weight, clinical indication), CT equipment (CT make and model, year of installation, number of detector rows), scan protocols (body region, scan phases, tube current and potential), and radiation dose descriptors (CT dose index and dose length product). Descriptive statistics and generalized estimating equations were performed. Results Data from 782 patients (median age, 59 years [interquartile range, 15 years]) from 54 health care sites in 28 countries were evaluated. Less than one-half of the health care sites used CT for initial diagnosis of COVID-19 pneumonia and three-fourths used CT for assessing disease severity. CT dose index varied based on CT vendors (7-11 mGy; P < .001), number of detector rows (8-9 mGy; P < .001), year of CT installation (7-10 mGy; P = .006), and reconstruction techniques (7-10 mGy; P = .03). Multiphase chest CT examinations performed at 20% of sites (11 of 54) were associated with higher dose length product compared with single-phase chest CT examinations performed in 80% of sites (43 of 54) (P = .008). Conclusion CT use, scan protocols, and radiation doses in patients with coronavirus disease 2019 pneumonia showed wide variation across health care sites within the same and between different countries. Many patients were imaged multiple times and/or with multiphase CT scan protocols. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Lee in this issue.
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