Pediatric Radiology

, Volume 45, Issue 10, pp 1544–1553 | Cite as

Limiting CT radiation dose in children with craniosynostosis: phantom study using model-based iterative reconstruction

  • Touko Kaasalainen
  • Kirsi Palmu
  • Anniina Lampinen
  • Vappu Reijonen
  • Junnu Leikola
  • Riku Kivisaari
  • Mika Kortesniemi
Original Article

Abstract

Background

Medical professionals need to exercise particular caution when developing CT scanning protocols for children who require multiple CT studies, such as those with craniosynostosis.

Objective

To evaluate the utility of ultra-low-dose CT protocols with model-based iterative reconstruction techniques for craniosynostosis imaging.

Materials and methods

We scanned two pediatric anthropomorphic phantoms with a 64-slice CT scanner using different low-dose protocols for craniosynostosis. We measured organ doses in the head region with metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters. Numerical simulations served to estimate organ and effective doses. We objectively and subjectively evaluated the quality of images produced by adaptive statistical iterative reconstruction (ASiR) 30%, ASiR 50% and Veo (all by GE Healthcare, Waukesha, WI). Image noise and contrast were determined for different tissues.

Results

Mean organ dose with the newborn phantom was decreased up to 83% compared to the routine protocol when using ultra-low-dose scanning settings. Similarly, for the 5-year phantom the greatest radiation dose reduction was 88%. The numerical simulations supported the findings with MOSFET measurements. The image quality remained adequate with Veo reconstruction, even at the lowest dose level.

Conclusion

Craniosynostosis CT with model-based iterative reconstruction could be performed with a 20-μSv effective dose, corresponding to the radiation exposure of plain skull radiography, without compromising required image quality.

Keywords

ALARA Computed tomography optimization Craniosynostosis Iterative reconstruction Child Radiation protection 

Supplementary material

247_2015_3348_MOESM1_ESM.doc (70 kb)
Table iMean subjective image quality rates of low-dose CT protocols using different reconstructions according to a 5-point Likert scale (DOC 70 kb)
247_2015_3348_Fig4_ESM.gif (26 kb)
Fig. i

Organ doses measured with MOSFET dosimeters at 100 kVp for the newborn (a) and (b) 5-year phantoms. Saturation of the tube current to a fixed minimum of 10 mA causes the regression curve model and the measurement results to diverge. MOSFET metal-oxide-semiconductor field-effect transistor (GIF 25 kb)

247_2015_3348_Fig5_ESM.gif (38 kb)
Fig. i

Organ doses measured with MOSFET dosimeters at 100 kVp for the newborn (a) and (b) 5-year phantoms. Saturation of the tube current to a fixed minimum of 10 mA causes the regression curve model and the measurement results to diverge. MOSFET metal-oxide-semiconductor field-effect transistor (GIF 25 kb)

247_2015_3348_MOESM2_ESM.eps (184 kb)
High resolution image (EPS 183 kb)
247_2015_3348_MOESM3_ESM.eps (124 kb)
High resolution image (EPS 124 kb)

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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Touko Kaasalainen
    • 1
    • 2
  • Kirsi Palmu
    • 1
    • 3
  • Anniina Lampinen
    • 1
    • 2
  • Vappu Reijonen
    • 1
  • Junnu Leikola
    • 4
  • Riku Kivisaari
    • 5
  • Mika Kortesniemi
    • 1
  1. 1.HUS Medical Imaging Center, RadiologyUniversity of Helsinki and Helsinki University HospitalHelsinkiFinland
  2. 2.Department of PhysicsUniversity of HelsinkiHelsinkiFinland
  3. 3.Department of Biomedical Engineering and Computational ScienceSchool of Science, Aalto UniversityHelsinkiFinland
  4. 4.Department of Plastic SurgeryUniversity of Helsinki and Helsinki University HospitalHelsinkiFinland
  5. 5.Department of NeurosurgeryUniversity of Helsinki and Helsinki University HospitalHelsinkiFinland

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