Pediatric Radiology

, Volume 47, Issue 6, pp 710–717 | Cite as

Image quality and radiation dose of brain computed tomography in children: effects of decreasing tube voltage from 120 kVp to 80 kVp

  • Ji Eun Park
  • Young Hun ChoiEmail author
  • Jung-Eun Cheon
  • Woo Sun Kim
  • In-One Kim
  • Hyun Suk Cho
  • Young Jin Ryu
  • Yu Jin Kim
Original Article



Computed tomography (CT) has generated public concern associated with radiation exposure, especially for children. Lowering the tube voltage is one strategy to reduce radiation dose.


To assess the image quality and radiation dose of non-enhanced brain CT scans acquired at 80 kilo-voltage peak (kVp) compared to those at 120 kVp in children.

Materials and methods

Thirty children who had undergone both 80- and 120-kVp non-enhanced brain CT were enrolled. For quantitative analysis, the mean attenuation of white and gray matter, attenuation difference, noise, signal-to-noise ratio, contrast-to-noise ratio and posterior fossa artifact index were measured. For qualitative analysis, noise, gray-white matter differentiation, artifact and overall image quality were scored. Radiation doses were evaluated by CT dose index, dose-length product and effective dose.


The mean attenuations of gray and white matter and contrast-to-noise ratio were significantly increased at 80 kVp, while parameters related to image noise, i.e. noise, signal-to-noise ratio and posterior fossa artifact index were higher at 80 kVp than at 120 kVp. In qualitative analysis, 80-kVp images showed improved gray-white differentiation but more artifacts compared to 120-kVp images. Subjective image noise and overall image quality scores were similar between the two scans. Radiation dose parameters were significantly lower at 80 kVp than at 120 kVp.


In pediatric non-enhanced brain CT scans, a decrease in tube voltage from 120 kVp to 80 kVp resulted in improved gray-white matter contrast, comparable image quality and decreased radiation dose.


Brain Children Computed tomography Dose reduction Ionizing radiation Tube voltage 


Compliance with ethical standards

Conflicts of interest



  1. 1.
    Yu L, Fletcher JG, Grant KL et al (2013) Automatic selection of tube potential for radiation dose reduction in vascular and contrast-enhanced abdominopelvic CT. AJR Am J Roentgenol 201:W297–W306CrossRefPubMedGoogle Scholar
  2. 2.
    Schauer DA, Linton OW (2009) National Council on Radiation Protection and Measurements Report shows substantial medical exposure increase. Radiology 253:293–296CrossRefPubMedGoogle Scholar
  3. 3.
    Brenner DJ, Hall EJ (2007) Computed tomography--an increasing source of radiation exposure. N Engl J Med 357:2277–2284CrossRefPubMedGoogle Scholar
  4. 4.
    Paterson A, Frush DP (2007) Dose reduction in paediatric MDCT: general principles. Clin Radiol 62:507–517CrossRefPubMedGoogle Scholar
  5. 5.
    Hall EJ (2002) Lessons we have learned from our children: cancer risks from diagnostic radiology. Pediatr Radiol 32:700–706CrossRefPubMedGoogle Scholar
  6. 6.
    Huda W, Atherton JV, Ware DE et al (1997) An approach for the estimation of effective radiation dose at CT in pediatric patients. Radiology 203:417–422CrossRefPubMedGoogle Scholar
  7. 7.
    Udayasankar UK, Braithwaite K, Arvaniti M et al (2008) Low-dose nonenhanced head CT protocol for follow-up evaluation of children with ventriculoperitoneal shunt: reduction of radiation and effect on image quality. AJNR Am J Neuroradiol 29:802–806CrossRefPubMedGoogle Scholar
  8. 8.
    McCollough CH, Primak AN, Braun N et al (2009) Strategies for reducing radiation dose in CT. Radiol Clin N Am 47:27–40CrossRefPubMedPubMedCentralGoogle Scholar
  9. 9.
    Ben-David E, Cohen JE, Nahum Goldberg S et al (2014) Significance of enhanced cerebral gray-white matter contrast at 80 kVp compared to conventional 120 kVp CT scan in the evaluation of acute stroke. J Clin Neurosci 21:1591–1594CrossRefPubMedGoogle Scholar
  10. 10.
    Brooks RA, Di Chiro G, Keller MR (1980) Explanation of cerebral white--gray contrast in computed tomography. J Comput Assist Tomogr 4:489–491CrossRefPubMedGoogle Scholar
  11. 11.
    Mullins ME, Lev MH, Bove P et al (2004) Comparison of image quality between conventional and low-dose nonenhanced head CT. AJNR Am J Neuroradiol 25:533–538PubMedGoogle Scholar
  12. 12.
    Pomerantz SR, Kamalian S, Zhang D et al (2013) Virtual monochromatic reconstruction of dual-energy unenhanced head CT at 65-75 keV maximizes image quality compared with conventional polychromatic CT. Radiology 266:318–325CrossRefPubMedGoogle Scholar
  13. 13.
    Rozeik C, Kotterer O, Preiss J et al (1991) Cranial CT artifacts and gantry angulation. J Comput Assist Tomogr 15:381–386CrossRefPubMedGoogle Scholar
  14. 14.
    Deak PD, Smal Y, Kalender WA (2010) Multisection CT protocols: sex- and age-specific conversion factors used to determine effective dose from dose-length product. Radiology 257:158–166CrossRefPubMedGoogle Scholar
  15. 15.
    Alvarez RE, Macovski A (1976) Energy-selective reconstructions in X-ray computerized tomography. Phys Med Biol 21:733–744CrossRefPubMedGoogle Scholar
  16. 16.
    Gnannt R, Winklehner A, Goetti R et al (2012) Low kilovoltage CT of the neck with 70 kVp: comparison with a standard protocol. AJNR Am J Neuroradiol 33:1014–1019CrossRefPubMedGoogle Scholar
  17. 17.
    Yu L, Bruesewitz MR, Thomas KB et al (2011) Optimal tube potential for radiation dose reduction in pediatric CT: principles, clinical implementations, and pitfalls. Radiographics 31:835–848CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  1. 1.Department of Radiology, Graduate SchoolKyung Hee University HospitalSeoulSouth Korea
  2. 2.Department of RadiologySeoul National University HospitalSeoulSouth Korea
  3. 3.Department of RadiologySeoul National University College of MedicineSeoulSouth Korea
  4. 4.Institute of Radiation MedicineSeoul National University Medical Research CenterSeoulSouth Korea

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