Radiation Doses in Consecutive CT Examinations from Five University of California Medical Centers

Rebecca Smith-Bindman; Michelle Moghadassi; Nicole Wilson; Thomas R Nelson; John M Boone; Christopher H Cagnon; Robert Gould; David J Hall; Mayil Krishnam; Ramit Lamba; Michael McNitt-Gray; Anthony Seibert; Diana L Miglioretti

doi:10.1148/radiol.2015142728

Radiation Doses in Consecutive CT Examinations from Five University of California Medical Centers

Radiology. 2015 Oct;277(1):134-41. doi: 10.1148/radiol.2015142728. Epub 2015 May 19.

Affiliation

¹ From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 350 Parnassus Ave, Suite 307C, San Francisco, CA 94143-0336 (R.S.B., M.M., N.W., R.G.); Department of Epidemiology and Biostatistics and the Philip R. Lee Institute for Health Policy Studies, University of California-San Francisco, San Francisco, Calif (R.S.B.); Department of Radiology, University of California-San Diego, San Diego, Calif (T.R.N., D.J.H.); Department of Radiology (J.M.B., R.L., A.S.) and Division of Biostatistics, Department of Public Health Sciences (D.L.M.), University of California-Davis, Davis, Calif; Department of Radiology, University of California-Los Angeles, Los Angeles, Calif (C.H.C., M.M.G.); Department of Radiological Sciences, University of California-Irvine, Irvine, Calif (M.K.); and Group Health Research Institute, Group Health Cooperative, Seattle, Wash (D.L.M.).

Abstract

Purpose: To summarize data on computed tomographic (CT) radiation doses collected from consecutive CT examinations performed at 12 facilities that can contribute to the creation of reference levels.

Materials and methods: The study was approved by the institutional review boards of the collaborating institutions and was compliant with HIPAA. Radiation dose metrics were prospectively and electronically collected from 199 656 consecutive CT examinations in 83 181 adults and 3871 consecutive CT examinations in 2609 children at the five University of California medical centers during 2013. The median volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose, along with the interquartile range (IQR), were calculated separately for adults and children and stratified according to anatomic region. Distributions for DLP and effective dose are reported for single-phase examinations, multiphase examinations, and all examinations.

Results: For adults, the median CTDIvol was 50 mGy (IQR, 37-62 mGy) for the head, 12 mGy (IQR, 7-17 mGy) for the chest, and 12 mGy (IQR, 8-17 mGy) for the abdomen. The median DLPs for single-phase, multiphase, and all examinations, respectively, were as follows: head, 880 mGy · cm (IQR, 640-1120 mGy · cm), 1550 mGy · cm (IQR, 1150-2130 mGy · cm), and 960 mGy · cm (IQR, 690-1300 mGy · cm); chest, 420 mGy · cm (IQR, 260-610 mGy · cm), 880 mGy · cm (IQR, 570-1430 mGy · cm), and 550 mGy · cm (IQR 320-830 mGy · cm); and abdomen, 580 mGy · cm (IQR, 360-860 mGy · cm), 1220 mGy · cm (IQR, 850-1790 mGy · cm), and 960 mGy · cm (IQR, 600-1460 mGy · cm). Median effective doses for single-phase, multiphase, and all examinations, respectively, were as follows: head, 2 mSv (IQR, 1-3 mSv), 4 mSv (IQR, 3-8 mSv), and 2 mSv (IQR, 2-3 mSv); chest, 9 mSv (IQR, 5-13 mSv), 18 mSv (IQR, 12-29 mSv), and 11 mSv (IQR, 6-18 mSv); and abdomen, 10 mSv (IQR, 6-16 mSv), 22 mSv (IQR, 15-32 mSv), and 17 mSv (IQR, 11-26 mSv). In general, values for children were approximately 50% those for adults in the head and 25% those for adults in the chest and abdomen.

Conclusion: These summary dose data provide a starting point for institutional evaluation of CT radiation doses.

Publication types

Multicenter Study

MeSH terms

Adolescent
Adult
California
Child
Child, Preschool
Hospitals, University
Humans
Infant
Prospective Studies
Radiation Dosage*
Tomography, X-Ray Computed / methods*

Radiation Doses in Consecutive CT Examinations from Five University of California Medical Centers

Authors

Affiliation

Abstract

Publication types

MeSH terms

Grants and funding