Radiation dose from CT scanning: can it be reduced?

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CT has been used to save many patients’ lives and the demand for CT is still increasing. At the same time, there has been increasing concern of the probability of cancer induction by CT radiation. It is necessary for everyone involved in CT scanning, particularly physicians who have to communicate with patients when planning a CT scan, to have a basic knowledge of the CT radiation dose and its potential adverse effects. We have undertaken a systematic review of the literatures to document the radiation dose from CT, the lifetime cancer risk from CT exposure, CT dose parameters, the internationnal CT diagnostic reference levels, and the use and limitation of the CT effective dose. In addition, we conducted a brief survey of the use of CT scan in some university hospitals in Thailand and estimated current CT doses at these hospitals. Our review and survey suggests that CT scanning provides a great benefit in medicine but it also becomes the major source of X-ray exposure. Radiation doses from a CT scan are much higher than most conventional radiographic procedures. This raises concerns about the carcinogenic potentials. We encourage every CT unit to adhere to the International Guidelines of CT dose parameter references. Our preliminary survey from some university hospitals in Thailand revealed that CT radiation doses are within acceptable standard ranges. However, the justification for utilization of CT scans should also be required and monitored. The importance of adequate communication between attending physician and consulting radiologist is stressed.

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  • 1. Berrington de Gonzalez 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: 2071-7.

  • 2. Sodickson A Baeyens PF Andriole KP Prevedello LM Naqfel RD Hanson R et al. Recurrent CT cumulative radiation exposure and associated radiation-induced cancer risks from CT of adults. Radiology. 2009; 251: 175-84.

  • 3. Hall EJ Brenner DJ. Cancer risks from diagnostic radiology. Br J Radiol. 2008; 81: 362-78.

  • 4. Brenner DJ Hall EJ. Computed tomography-an increasing source of radiation exposure. N Engl J Med. 2007; 357: 2277-84.

  • 5. Little MP. Risks associated with ionizing radiation. Br Med Bull. 2003; 68: 259-275

  • 6. Balter S Hopewell JW Miller DL Wagner LK Zelefsky MJ. Fluoroscopically guided interventional procedures: a review of radiation effects on patients’ skin and hair. Radiology. 2010; 254:326-41.

  • 7. Bor D Olgar T Toklu T Caglan A Onal E Padovani R. Patient doses and dosimetric evaluations in interventional cardiology. Phys Med. 2009; 25: 31-42.

  • 8. Smith-Bindman R. Is computed tomography safe? N Engl J Med. 2010; 363:1-4.

  • 9. Mettler FA Jr Huda W Yoshizumi TY Mahesh M. Effective doses in radiology and diagnostic nuclear medicine: a catalog. Radiology. 2008; 248:254-63.

  • 10. International Commission of Radiation Protection. The 2007 recommendations of the international commission on radiological protection. ICRP Publication 103. Ann. ICRP. 2007; 37:1-332.

  • 11. Richards PJ George J Metelko M Brown M. Spine computed tomography dose and cancer induction. Spine 2010; 35:430-3.

  • 12. IAEA: Radiation protection of patients (RPOP): Information for X-ray. Available from: http://rpop.iaea.org/RPOP/RPoP/Content/InformationFor/Patients/patient-information-x-rays/index.htm.

  • 13. Preston DL Ron E Tokuoka S Funamoto S Nishi N Soda M et al. Solid cancer incidence in atomic bomb survivors: 1958-1999. Radiat Res. 2007; 168: 1-64.

  • 14. Little MP. Cancer and non-cancer effects in Japanese atomic bomb survivors. J Radiol Prot. 2009; 29: A43-59.

  • 15. Hoffman DA Lonstein JE Morin MM Visscher W Harris BS 3rd Boice JD Jr. Breast cancer in women with scoliosis exposed to multiple diagnostic X-rays. J Natl Cancer Inst. 1989 81: 1307-12.

  • 16. Doody M Lonstein JE Stovall M Hacker DJ Luckyanov N Land CE. Breast cancer mortality after diagnostic radiography: findings from the U.S. Scoliosis Cohort Study. Spine. 2000; 25: 2052-63.

  • 17. Infante-Rivard C. Diagnostic x rays DNA repair genes and childhood acute lymphoblastic leukemia. Health Phys. 2003; 85: 60-4.

  • 18. Ron E. Cancer risks from medical radiation. Health Phys. 2003; 85: 47-59.

  • 19. Kleinerman RA. Cancer risks following diagnostic and therapeutic radiation exposure in children. Pediatr Radiol. 2006; 36 Suppl 2: 121-5.

  • 20. Preston RJ. Update on linear non-threshold doseresponse model and implications for diagnostic radiologic procedures. Health Physics. 2008; 95: 541-6.

  • 21. Martin CJ. Effective dose: how should it be applied to medical exposure? Br J Radiol. 2007; 80: 639-47.

  • 22. National Radiological Protection Board. Board statement on diagnostic medical exposures to ionizing radiation during pregnancy and estimates of late radiation risks to the UK population. Documents of the NRPB vol 4 No. 4. Chilton: NRPB 1993.

  • 23. Rannikko S Ermakov I Lampinen JS Toivonen M Darila KTK Chervjakov A. Computing patient doses of X-ray examinations using a patient size- and sexadjustable phantom. Br J Radiol. 1997; 70: 708-18.

  • 24. European Commission. European guidelines on quality criteria for computed tomography. EUR 16262 EN Luxembourg 1999.

  • 25. European Commission. European quality criteria for multislice CT. Luxembourg 2004.

  • 26. Hatziioannou K Papanastassiou E Delichas M Bousbouras P. A contribution to establishment of diagnostic reference levels in CT. Br J Radiol. 2003; 76: 541-5.

  • 27. Kiljunen T Tietavainen A Parviainen T Viitala A Kortesniemi M. Organ doses and effective doses in pediatric radiography: patient-dose survey in Finland. Acta Radiol. 2009; 50: 114-24.

  • 28. Kharita MH Khazzam S. Survey of patient dose in computed tomography in Syria 2009. Radiat Prot Dosimetry 2010; 1-13.

  • 29. Choi J Cha S Lee K Shin D Kang J Kim Y et al. The development of a guidance level for patient dose for CT examinations in Korea. Radiat Prot Dosimetry. 2010; 138: 137-43.

  • 30. Shrimpton PC Hillier MC Lewis MA Dunn M. National survey of doses from CT in the UK: 2003.Br J Radiol. 2006; 79: 968-80.

  • 31. Rehani MM. Radiation protection in newer imaging technologies. Radiat Prot Dosimetry. 2010; 139: 357-62.

  • 32. Harrison JD Streffer C. The ICRP protection quantities equivalent and effective dose: there basis and application. Radiation Protection Dosimetry. 2007; 127: 12-18.

  • 33. McCollough CH Christner JA Kofler JM. How effective is effective dose as a predictor of radiation risk? Am J Roentgenol. 2010; 194: 890-6.

  • 34. Christner JA Kofler JM McCollough CH. Estimating effective dose for CT using dose-length product compared with using organ doses: consequences of adopting International Commission on Radiological Protection publication 103 or dual-energy scanning. Am J Roentgenol. 2010; 194: 881-9.

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