Dose Optimization and Reduction in CT of Children

  • Peter Vock
  • Enno Stranzinger
  • Rainer Wolf
Part of the Medical Radiology book series (MEDRAD)


Children differ from adult patients in that they vary tremendously in their small size—which mandates adaptation of physical scan parameters—but also in their elevated susceptibility to ionizing radiation, and the different pathology during childhood. While the many technical innovations in CT during the last decade have impacted the entire field of clinical applications, faster scanning in children often makes the difference by eliminating motion artifacts; a number of new features contribute to reducing radiation exposure of children, most importantly iterative reconstruction and adaptive dose shielding. Limited cooperation of children often influences image quality more significantly than the choice of scanning parameters. Decreasing anxiety, avoiding pain, exercising cooperation before the scan, and avoiding artifacts by eliminating foreign bodies from the scan field are measures of high importance; a child-friendly atmosphere and staff further contribute to a successful scan. Choosing appropriate pediatric protocols means using each feature of a specific scanner to the best of the individual child, often accepting noise, scanning the minimal length and avoiding repeat/multiphase scans of the same volume. It is suggested to start with a scanner-optimized adult abdominal or head scan protocol and to reduce mAs according to tables available in the internet. In addition, lowering tube voltage is an excellent tool for high-contrast organs and CT angiography in children. Radiation risks based on biology and physics have been covered in previous chapters and are, of course, also valid for children. Similarly, clinical approaches to dose optimization and reduction are similar in pediatric and adult CT examinations (Huda et al., Pediatr Radiol 32:272–279, 2000). This chapter will concentrate on the fact that children are not just adults with smaller dimensions, thus it will point out what is special in children.


Radiation Exposure Iterative Reconstruction Dose Modulation Automatic Exposure Control Diagnostic Reference Level 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors thank Barbara Le Blanc for typing the manuscript and Mannudeep Kalra for contributing important suggestions on protocol definition.


  1. AAPM Report No. 204 (2011) Size-specific dose estimates (SSDE) in pediatric and adult body CT examinations. American Association of Physicists in Medicine, ISBN: 978-1-936366-08-8. Accessed 12 December 2011
  2. American College of Radiology (2011) ACR appropriateness criteria, diagnostic imaging topics. Accessed 15 November 2011
  3. Beaconsfield T, Nicholson R, Thornton A, Al-Kutoubi A (1998) Would thyroid and breast shielding be beneficial in CT of the head? Eur Radiol 8:664–667PubMedCrossRefGoogle Scholar
  4. Boone JM, Geraghty EM, Seibert JA, Wootton-Gorges SL (2003) Dose reduction in pediatric CT: a rational approach. Radiology 228:352–360PubMedCrossRefGoogle Scholar
  5. Brenner DJ (2002) Estimating cancer risks from pediatric CT: going from the qualitative to the quantitative. Pediatr Radiol 32:228–231PubMedCrossRefGoogle Scholar
  6. Brenner DJ, Elliston CD, Hall EJ, Berdon WE (2001) Estimated risks of radiation—induced fatal cancer from pediatric CT. AJR Am J Roentgenol 176:289–296PubMedGoogle Scholar
  7. Brenner DJ, Doll R, Goodhead DT, Hall EJ, Land CE, Little JB, Lubin JH, Preston DL, Preston RJ, Puskin JS, Ron E, Sachs RK, Samet JM, Setlow RB, Zaider M (2003) Cancer risks attributable to low doses of ionizing radiation: assessing what we really know. Proc Natl Acad Sci U S A 100:13761–13766PubMedCrossRefGoogle Scholar
  8. Brnic Z, Vekic B, Hebrang A, Anic P (2003) Efficacy of breast shielding during CT of the head. Eur Radiol 13:2436–2440PubMedCrossRefGoogle Scholar
  9. Campbell J, Kaira MK, Rizzo S, Maher MM, Shepard JA (2005) Scanning beyond anatomic limits of the thorax in chest CT: findings, radiation dose, and automatic tube current modulation. J Roentgenol AJR 185:1525–1530CrossRefGoogle Scholar
  10. Chapple CL, Willis S, Frame J (2002) Effective dose in paediatric computed tomography. Phys Med Biol 47:107–115PubMedCrossRefGoogle Scholar
  11. Cody DD, Moxley DM, Krugh KT, O’Daniel JC, Wagner LK, Eftekhari F (2004) Strategies for formulating appropriate MDCT techniques when imaging the chest, abdomen, and pelvis in pediatric patients. Am J Roentgenol AJR 182:849–859Google Scholar
  12. Donnelly LF, Emery KH, Brody AS, Laor T, Gylys-Morin VM, Anton GA, Thomas SR, Frush DP (2001) Minimizing radiation dose for pediatric body applications of single-detector helical CT: strategies at a large children’s hospital. AJR Am J Roentgenol 176:303–306PubMedGoogle Scholar
  13. European Commission (2000) European guidelines on quality criteria for computed tomography, EUR 16262EN. Office for Official Publications of the European Communities, Luxembourg. Accessed 15 Nov 2011
  14. Fishman EK (2011) CTisus, Pediatric protocols. Accessed 15 November 2011
  15. Fricke BL, Donnelly LF, Frush DP, Yoshizumi T, Varchena V, Poe SA, Lucaya J (2003) In-plane bismuth breast shields for pediatric CT: effects on radiation dose and image quality using experimental and clinical data. Am J Roentgenol AJR 180:407–411Google Scholar
  16. Frush DP, Soden B, Frush KS, Lowry C (2002) Improved pediatric multidetector CT using a size-based color-coded format. AJR Am J Roentgenol 178:721–726PubMedGoogle Scholar
  17. Frush DP, Donnelly LF, Rosen NS (2003) Computed tomography and radiation risks: what pediatric health care providers should know. Pediatrics 112:951–957PubMedCrossRefGoogle Scholar
  18. Greess H, Lutze J, Nömayr A, Wolf H, Hothorn T, Kalender WA, Bautz W (2004) Dose reduction in subsecond multislice spiral CT examination of children by online tube current modulation. Eur Radiol 14:995–999PubMedCrossRefGoogle Scholar
  19. Han BK, Lindberg J, Grant K, Schwartz RS, Lesser JR (2011) Accuracy and safety of high pitch computed tomography imaging in young children with complex congenital heart disease. Am J Cardiol 107:1541–1546PubMedCrossRefGoogle Scholar
  20. Hidajat N, Schroder RJ, Vogl T, Schedel H, Felix R (1996) The efficacy of lead shielding in patient dosage reduction in computed tomography (German). Rofo 165:462–465PubMedCrossRefGoogle Scholar
  21. Hohl C, Mahnken AH, Klotz E, Das M, Stargardt A, Mühlenbruch G, Schmidt T, Günther RW, Wildberger JE (2005) Radiation dose reduction to the male gonads during MDCT: the effectiveness of a lead shield. Am J Roentgenol AJR 184:128–130Google Scholar
  22. Hopper KD, King SH, Lobell ME, TenHave TR, Weyver JS (1997) Rhe breast: in-plane x-ray protection during diagnostic thoracic CT—shielding with bismuth radioprotective garments. Radiology 205:853–858PubMedGoogle Scholar
  23. Huda W (2002) Effective dose to adult and pediatric patients. Pediatr Radiol 32:272–279PubMedCrossRefGoogle Scholar
  24. Huda W, Scalzetti EM, Levin G (2000) Technique factors and image quality as functions of patient weight at abdominal CT. Radiology 217:430–435PubMedGoogle Scholar
  25. Image gently (2007). The alliance for radiation safety in pediatric imaging. Pediatric CT Protocol Guidance. Accessed 15 Nov 2011
  26. Kalra MK, Maher MM, Blake MA, Lucey BC, Karau K, Toth TL, Gopal A, Halpern EF, Saini S (2004) Detection and characterization of lesions on low-radition-dose abdominal CT images postprocessed with noise reduction filters. Radiology 232:791–797PubMedCrossRefGoogle Scholar
  27. Lell MM, May M, Deak P, Alibek S, Kuefner M, Kuettner A, Köhler H, Achenbach S, Uder M, Radkow T (2011) High-pitch spiral computed tomography: effect on image quality and radiation does in pediatric chest computed tomography. Invest Radiol 46:116–123PubMedCrossRefGoogle Scholar
  28. Mettler FA, Wiest PW, Locken JA, Kelsey CA (2000) CT scanning: patterns of use and dose. J Radiol Prot 20:353–359PubMedCrossRefGoogle Scholar
  29. Miéville FA, Gudinchet F, Rizzo E, Ou P, Brunelle F, Bochud FO, Verdun FR (2011) Paediatric cardiac CT examinations: impact of the iterative reconstruction method ASIR on image quality—preliminary findings. Pediatr Radiol 41:1154–1164PubMedCrossRefGoogle Scholar
  30. Nauer CB, Rieke A, Zubler C, Candreia C, Arnold A, Senn P (2011) Low-dose temporal bone CT in infants and young children: effective dose and image quality. AJNR Am J Neuroradiol 32(8):1375–1380PubMedCrossRefGoogle Scholar
  31. Nickoloff E (2002) Current adult and pediatric CT doses. Pediatr Radiol 32:250–260PubMedCrossRefGoogle Scholar
  32. Nickoloff EL, Alderson PO (2001) Radiation exposures to patients from CT. Reality, public perception, and policy. AJR Am J Roentgenol 177:285–287PubMedGoogle Scholar
  33. Oman JA, Cooper RJ, Holmes JF, Viccellio P, Nyce A, Ross SE et al (2006) for the NEXUS II investigators, Performance of a decision rule to predict need for Computed tomography among children with blunt head trauma. Pediatrics 117:238–246CrossRefGoogle Scholar
  34. Pages J, Buls N, Osteaux M (2003) CT doses in children: a multicentre study. Brit J Radiol 76:803–811PubMedCrossRefGoogle Scholar
  35. Paterson A, Frush DP, Donnelly LF (2001) Helical CT of the body: are settings adjusted for pediatric patients? AJR 176:297–301PubMedGoogle Scholar
  36. Pierce DA, Preston DL (2000) Radiation-related cancer risks at low doses among atomic bomb survivors. Radiat Res 154:178–186PubMedCrossRefGoogle Scholar
  37. Price R, Halson P, Sampson M (1999) Dose reduction during CT scanning in an anthropomorphic phantom by the use of a male gonad shield. Br J Radiol 72:489–494PubMedGoogle Scholar
  38. Ravenel JG, Scalzetti EM, Huda W, Garrisi W (2001) Radiation exposure and image quality in chest CT examinations. AJR 177:279–284PubMedGoogle Scholar
  39. RCR Referral guidelines (2007) Making the best use of clinical radiology, 7th edn. MBUR7. 15 Nov 2011
  40. Shah R, Gupta AK, Rehani MM, Pandey AK, Mukhopadhyay S (2005) Effect of reduction in tube current on reader confidence in paediatric computed tomography. Clin Radiol 60:224–231PubMedCrossRefGoogle Scholar
  41. Shrimpton PC, Wall BF (2000) Reference doses for paediatric computed tomography. Radiat Prot Dosim 90:249–252CrossRefGoogle Scholar
  42. Shrimpton PC, Hillier MC, Lewis MA, Dunn M (2005) Doses from computed tomography (CT) examinations in the UK—2003 review. UK Health protection agency, NRPB-W67Google Scholar
  43. Slovis TL (2002) The ALARA (as low as reasonably achievable) concept in pediatric CT intelligent dose reduction, ALARA conference proceedings. Pediatr Radiol 32:219–220CrossRefGoogle Scholar
  44. Slovis TL (2003) Children, computed tomography radiation dose, and the As low as reasonably achievable (ALARA) concept. Pediatrics 112:971–972PubMedCrossRefGoogle Scholar
  45. Tack D, De Maertelaer V, Gevenois PA (2003) Dose reduction in multidetector CT using attenuation-based online tube current modulation. Am J Roentgenol AJR 181:331–334Google Scholar
  46. Vock P (2002) CT radiation exposure in children: consequences of the American discussion for Europe (German). Radiologe 42:697–702PubMedCrossRefGoogle Scholar
  47. Vock P (2005) CT dose reduction in children. Eur Radiol 15:2330–2340PubMedCrossRefGoogle Scholar
  48. Vorona GA, Ceschin RC, Clayton BL, Sutcavage T, Tadros SS, Panigrahy A (2011) Reducing abdominal CT radiation dose with the adaptive statistical iterative reconstruction technique in children: a feasibility study. Pediatr Radiol 41:1174–1182PubMedCrossRefGoogle Scholar
  49. Wall BF (2001) Diagnostic reference levels—the way forward, commentary. Brit J Radiol 74:785–788PubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Department of Diagnostic, Interventional and Pediatric RadiologyUniversity Hospital, InselspitalBernSwitzerland

Personalised recommendations