Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate, Inc. and/or its affiliates. All Rights Reserved.

Radiation-related risks of imaging studies

Christoph I Lee, MD, MS
Joann G Elmore, MD, MPH
Section Editor
Mark D Aronson, MD
Deputy Editor
Howard Libman, MD, FACP


Ionizing radiation from medical imaging now accounts for nearly half of the radiation exposure experienced by the population in the United States [1,2]. Medical imaging may contribute less to total radiation exposure in other countries, however; 2005 data from the United Kingdom, for example, suggest that an average annual dose of imaging accounted for approximately one-sixth of annual exposure to ionizing radiation [3].

This topic will present an overview of the measurement of radiation associated with medical imaging, the effects of radiation exposure, the radiation associated with specific diagnostic imaging studies, and issues in clinical decision-making, including informed consent. Other related topics, including discussions of radiation injury, diagnostic imaging in pregnancy, and radiation exposure in cardiovascular imaging are presented separately.

(See "Biology and clinical features of radiation injury in adults".)

(See "Diagnostic imaging procedures during pregnancy".)

(See "Radiation dose and risk of malignancy from cardiovascular imaging".)

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information on subscription options, click below on the option that best describes you:

Subscribers log in here

Literature review current through: Sep 2017. | This topic last updated: Jun 19, 2015.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
  1. National Council on Radiation Protection and Measurements. Ionizing radiation exposure of the population of the United States. Report, Bethesda, MD 2009.
  2. Brenner DJ, Hall EJ. Computed tomography--an increasing source of radiation exposure. N Engl J Med 2007; 357:2277.
  3. Ionising radiation exposure of the UK population: 2005 review. Health Protection Agency. http://www.hpa.nhs.uk/web/HPAweb&HPAwebStandard/HPAweb_C/1247816567393.
  4. Mettler FA Jr, Bhargavan M, Faulkner K, et al. Radiologic and nuclear medicine studies in the United States and worldwide: frequency, radiation dose, and comparison with other radiation sources--1950-2007. Radiology 2009; 253:520.
  5. Smith-Bindman R, Miglioretti DL, Johnson E, et al. Use of diagnostic imaging studies and associated radiation exposure for patients enrolled in large integrated health care systems, 1996-2010. JAMA 2012; 307:2400.
  6. Lee J, Kirschner J, Pawa S, et al. Computed tomography use in the adult emergency department of an academic urban hospital from 2001 to 2007. Ann Emerg Med 2010; 56:591.
  7. The 2007 Recommendations of the International Commission on Radiological Protection. ICRP publication 103. Ann ICRP 2007; 37:1.
  8. Bolus NE. Basic review of radiation biology and terminology. J Nucl Med Technol 2001; 29:67.
  9. Dowd SB, Tilson ER. Practical Radiation Protection and Applied Radiobiology, 2nd ed, Saunders, Philadelphia 1999.
  10. Radiation and your patient: a guide for medical practitioners. Ann ICRP 2001; 31:5.
  11. Ladou J. Occupational Medicine, Appleton & Lange, Norwalk, CT 1990.
  12. NCRP. Evaluation of the linear nonthreshold dose-response model for ionizing radiation. Report No 136, National Council on Radiation Protection and Measurements, Bethesda, MD 2001.
  13. Hall EJ, Brenner DJ. Cancer risks from diagnostic radiology. Br J Radiol 2008; 81:362.
  14. International Marketing Ventures. 2006 CT Market Summary Report. Rockville, MD; 2006. Available at: http://www.imvinfo.com (Accessed on July 24, 2010).
  15. Feinendegen LE. Evidence for beneficial low level radiation effects and radiation hormesis. Br J Radiol 2005; 78:3.
  16. Ray P, Vu T, Romero M, Perrier ND. Limiting the risks of radiation exposure in diagnostic imaging. Surgery 2014; 156:1297.
  17. Huda W. Kerma-area product in diagnostic radiology. AJR Am J Roentgenol 2014; 203:W565.
  18. Fazel R, Krumholz HM, Wang Y, et al. Exposure to low-dose ionizing radiation from medical imaging procedures. N Engl J Med 2009; 361:849.
  19. Pierce DA, Preston DL. Radiation-related cancer risks at low doses among atomic bomb survivors. Radiat Res 2000; 154:178.
  20. Preston DL, Ron E, Tokuoka S, et al. Solid cancer incidence in atomic bomb survivors: 1958-1998. Radiat Res 2007; 168:1.
  21. Brenner DJ, Doll R, Goodhead DT, et al. Cancer risks attributable to low doses of ionizing radiation: assessing what we really know. Proc Natl Acad Sci U S A 2003; 100:13761.
  22. Miller AB, Howe GR, Sherman GJ, et al. Mortality from breast cancer after irradiation during fluoroscopic examinations in patients being treated for tuberculosis. N Engl J Med 1989; 321:1285.
  23. Cardis E, Vrijheid M, Blettner M, et al. The 15-Country Collaborative Study of Cancer Risk among Radiation Workers in the Nuclear Industry: estimates of radiation-related cancer risks. Radiat Res 2007; 167:396.
  24. The National Academies. Health risks from exposure to low levels of ionizing radiation: BEIR VII phase 2. Available at: http://www.nap.edu (Accessed on July 30, 2010).
  25. Task Group on Control of Radiation Dose in Computed Tomography. Managing patient dose in computed tomography. A report of the International Commission on Radiological Protection. Ann ICRP 2000; 30:7.
  26. Berrington de González A, Mahesh M, Kim KP, et al. Projected cancer risks from computed tomographic scans performed in the United States in 2007. Arch Intern Med 2009; 169:2071.
  27. Smith-Bindman R, Lipson J, Marcus R, et al. Radiation dose associated with common computed tomography examinations and the associated lifetime attributable risk of cancer. Arch Intern Med 2009; 169:2078.
  28. Brenner DJ, Elliston CD. Estimated radiation risks potentially associated with full-body CT screening. Radiology 2004; 232:735.
  29. Kroeker KI, Lam S, Birchall I, Fedorak RN. Patients with IBD are exposed to high levels of ionizing radiation through CT scan diagnostic imaging: a five-year study. J Clin Gastroenterol 2011; 45:34.
  30. Mettler FA Jr, Huda W, Yoshizumi TT, Mahesh M. Effective doses in radiology and diagnostic nuclear medicine: a catalog. Radiology 2008; 248:254.
  31. Shrimpton PC, Hillier MC, Lewis MA, Dunn M. National survey of doses from CT in the UK: 2003. Br J Radiol 2006; 79:968.
  32. Diederich S, Lenzen H. Radiation exposure associated with imaging of the chest: comparison of different radiographic and computed tomography techniques. Cancer 2000; 89:2457.
  33. Lin EC. Radiation risk from medical imaging. Mayo Clin Proc 2010; 85:1142.
  34. Jones DG, Shrimpton PC. Survey of CT practice in the UK. Part 3: Normalised organ doses calculated using Monte Carlo techniques. NRPB R-250. Chilton, England: National Radiological Protection Board, 1992.
  35. Frush DP. Review of radiation issues for computed tomography. Semin Ultrasound CT MR 2004; 25:17.
  36. Smith-Bindman R. Environmental causes of breast cancer and radiation from medical imaging: findings from the Institute of Medicine report. Arch Intern Med 2012; 172:1023.
  37. McCollough CH, Primak AN, Braun N, et al. Strategies for reducing radiation dose in CT. Radiol Clin North Am 2009; 47:27.
  38. Amis ES Jr, Butler PF, Applegate KE, et al. American College of Radiology white paper on radiation dose in medicine. J Am Coll Radiol 2007; 4:272.
  39. ACR appropriateness criteria www.acr.org/SecondaryMainMenuCategories/quality_safety/app_criteria.aspx.
  40. The Royal college of Radiologists. Making the best use of clinical radiology services (MBUR6). http://www.rcr.ac.uk/content.aspx?PageID=995.
  41. The European Commission. Referral guidelines for imaging. http://ec.europa.eu/energy/nuclear/radioprotection/publication/doc/118_en.pdf.
  42. Hall EJ. Lessons we have learned from our children: cancer risks from diagnostic radiology. Pediatr Radiol 2002; 32:700.
  43. Vartanians VM, Sistrom CL, Weilburg JB, et al. Increasing the appropriateness of outpatient imaging: effects of a barrier to ordering low-yield examinations. Radiology 2010; 255:842.
  44. Rosenthal DI, Weilburg JB, Schultz T, et al. Radiology order entry with decision support: initial clinical experience. J Am Coll Radiol 2006; 3:799.
  45. Sistrom CL, Dang PA, Weilburg JB, et al. Effect of computerized order entry with integrated decision support on the growth of outpatient procedure volumes: seven-year time series analysis. Radiology 2009; 251:147.
  46. Callahan MJ. CT dose reduction in practice. Pediatr Radiol 2011; 41 Suppl 2:488.
  47. Brenner DJ, Hricak H. Radiation exposure from medical imaging: time to regulate? JAMA 2010; 304:208.
  48. Radiation Reporting: California Senate Bill 1237 (2010). Available at: http://www.leginfo.ca.gov/pub/09-10/bill/sen/sb_1201-1250/sb_1237_bill_20100902_enrolled.pdf (Accessed on February 02, 2012).
  49. US Food and Drug Administration. White paper: initiative to reduce unnecessary radiation exposure from medical imaging. http://www.fda.gov/Radiation-EmittingProducts/RadiationSafety/RadiationDoseReduction/ucm199994.htm (Accessed on February 17, 2011).
  50. Committee on Medical Aspects of Radiation in the Environment (COMPARE). 2007. http://www.comare.org.uk/documents/COMARE12thReport.pdf.
  51. Brink JA, Amis ES Jr. Image Wisely: a campaign to increase awareness about adult radiation protection. Radiology 2010; 257:601.
  52. American College of Radiology. ACR in Choosing Wisely Campaign to Promote Wise Use of Resources Among Physicians and Patients. Available at: http://www.acr.org/HomePageCategories/News/ACRNewsCenter/ACR-Joins-Choosing-Wisely.aspx (Accessed on February 02, 2012).
  53. Rao VM, Levin DC. The overuse of diagnostic imaging and the Choosing Wisely initiative. Ann Intern Med 2012; 157:574.
  54. RadiologyInfo.org http://www.radiologyinfo.org/en/safety/index.cfm?pg=sfty_xray (Accessed on May 13, 2011).
  55. Hohl C, Wildberger JE, Süss C, et al. Radiation dose reduction to breast and thyroid during MDCT: effectiveness of an in-plane bismuth shield. Acta Radiol 2006; 47:562.
  56. Yilmaz MH, Albayram S, Yaşar D, et al. Female breast radiation exposure during thorax multidetector computed tomography and the effectiveness of bismuth breast shield to reduce breast radiation dose. J Comput Assist Tomogr 2007; 31:138.
  57. Parker MS, Kelleher NM, Hoots JA, et al. Absorbed radiation dose of the female breast during diagnostic multidetector chest CT and dose reduction with a tungsten-antimony composite breast shield: preliminary results. Clin Radiol 2008; 63:278.
  58. Geleijns J, Salvadó Artells M, Veldkamp WJ, et al. Quantitative assessment of selective in-plane shielding of tissues in computed tomography through evaluation of absorbed dose and image quality. Eur Radiol 2006; 16:2334.
  59. Hohl C, Mahnken AH, Klotz E, et al. Radiation dose reduction to the male gonads during MDCT: the effectiveness of a lead shield. AJR Am J Roentgenol 2005; 184:128.
  60. Grobe H, Sommer M, Koch A, et al. Dose reduction in computed tomography: the effect of eye and testicle shielding on radiation dose measured in patients with beryllium oxide-based optically stimulated luminescence dosimetry. Eur Radiol 2009; 19:1156.
  61. Dunnick NR, Applegate KE, Arenson RL. The inappropriate use of imaging studies: a report of the 2004 Intersociety Conference. J Am Coll Radiol 2005; 2:401.
  62. Swensen SJ. Patient-centered Imaging. Am J Med 2012; 125:115.
  63. Lee CI, Haims AH, Monico EP, et al. Diagnostic CT scans: assessment of patient, physician, and radiologist awareness of radiation dose and possible risks. Radiology 2004; 231:393.
  64. American Association of Physicists in Medicine. The Measurement, Reporting, and Management of Radiation Dose in CT: Report of AAPM Task Group 23 of the Diagnostic Imaging Council CT Committee. College Park, MD: American Association of Physicists in Medicine; 2008. AAPM report 96.
  65. Brink JA, Goske MJ, Patti JA. Informed decision making trumps informed consent for medical imaging with ionizing radiation. Radiology 2012; 262:11.
  66. Lee CI, Flaster HV, Haims AH, et al. Diagnostic CT scans: institutional informed consent guidelines and practices at academic medical centers. AJR Am J Roentgenol 2006; 187:282.
  67. Safety investigation of CT brain perfusion scans: Update 11/9/2010. http://www.fda.gov/MedicalDevices/Safety/AlertsandNotices/ucm185898.htm (Accessed on November 23, 2010).
  68. Baerlocher MO, Detsky AS. Discussing radiation risks associated with CT scans with patients. JAMA 2010; 304:2170.
  69. Illes J, Fan E, Koenig BA, et al. Self-referred whole-body CT imaging: current implications for health care consumers. Radiology 2003; 228:346.
  70. Brenner DJ. Radiation risks potentially associated with low-dose CT screening of adult smokers for lung cancer. Radiology 2004; 231:440.
  71. Winchester DE, Wymer DC, Shifrin RY, et al. Responsible use of computed tomography in the evaluation of coronary artery disease and chest pain. Mayo Clin Proc 2010; 85:358.
  72. Bach PB, Mirkin JN, Oliver TK, et al. Benefits and harms of CT screening for lung cancer: a systematic review. JAMA 2012; 307:2418.
  73. Linet MS, Kim KP, Rajaraman P. Children's exposure to diagnostic medical radiation and cancer risk: epidemiologic and dosimetric considerations. Pediatr Radiol 2009; 39 Suppl 1:S4.
  74. Brenner D, Elliston C, Hall E, Berdon W. Estimated risks of radiation-induced fatal cancer from pediatric CT. AJR Am J Roentgenol 2001; 176:289.
  75. Chen JX, Kachniarz B, Gilani S, Shin JJ. Risk of malignancy associated with head and neck CT in children: a systematic review. Otolaryngol Head Neck Surg 2014; 151:554.
  76. Pearce MS, Salotti JA, Little MP, et al. Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumours: a retrospective cohort study. Lancet 2012; 380:499.
  77. Wakeford R, Little MP. Risk coefficients for childhood cancer after intrauterine irradiation: a review. Int J Radiat Biol 2003; 79:293.
  78. Preston DL, Cullings H, Suyama A, et al. Solid cancer incidence in atomic bomb survivors exposed in utero or as young children. J Natl Cancer Inst 2008; 100:428.
  79. Mehta P, Smith-Bindman R. Airport full-body screening: what is the risk? Arch Intern Med 2011; 171:1112.
  80. Hupe O, Ankerhold U. X-ray security scanners for personnel and vehicle control: dose quantities and dose values. Eur J Radiol 2007; 63:237.
  81. Brenner DJ. Are x-ray backscatter scanners safe for airport passenger screening? For most individuals, probably yes, but a billion scans per year raises long-term public health concerns. Radiology 2011; 259:6.
  82. Schauer DA. Does security screening with backscatter x-rays do more good than harm? Radiology 2011; 259:12.