Advertisement

Neuroradiology

, Volume 59, Issue 2, pp 169–176 | Cite as

Radiation dose reduction in parasinus CT by spectral shaping

  • Matthias S May
  • Michael Brand
  • Michael M Lell
  • Martin Sedlmair
  • Thomas Allmendinger
  • Michael Uder
  • Wolfgang WuestEmail author
Head and Neck Radiology

Abstract

Introduction

Spectral shaping aims to narrow the X-ray spectrum of clinical CT. The aim of this study was to determine the image quality and the extent of radiation dose reduction that can be achieved by tin prefiltration for parasinus CT.

Methods

All scans were performed with a third generation dual-source CT scanner. A study protocol was designed using 100 kV tube voltage with tin prefiltration (200 mAs) that provides image noise levels comparable to a low-dose reference protocol using 100 kV without spectral shaping (25 mAs). One hundred consecutive patients were prospectively enrolled and randomly assigned to the study or control group. All patients signed written informed consent. The study protocol was approved by the local Institutional Review Board and applies to the HIPAA. Subjective and objective image quality (attenuation values, image noise, and contrast-to-noise ratio (CNR)) were assessed. Radiation exposure was assessed as volumetric CT dose index, and effective dose was estimated. Mann-Whitney U test was performed for radiation exposure and for image noise comparison.

Results

All scans were of diagnostic image quality. Image noise in air, in the retrobulbar fat, and in the eye globe was comparable between both groups (all p > 0.05). CNReye globe/air did not differ significantly between both groups (p = 0.7). Radiation exposure (1.7 vs. 2.1 mGy, p < 0.01) and effective dose (0.055 vs. 0.066 mSv, p < 0.01) were significantly reduced in the study group.

Conclusion

Radiation dose can be further reduced by 17% for low-dose parasinus CT by tin prefiltration maintaining diagnostic image quality.

Keywords

Parasinus CT Tin filtration Spectral shaping 

Notes

Acknowledgements

We thank Petra Ruse and Katharina Roth for excellent patient management and Marie-Louise Haider for assistance in data management. This study was supported by the German government, Bundesministerium für Bildung und Forschung (01EX1012B, Spitzencluster Medical Valley).

Compliance with ethical standards

We declare that all human and animal studies have been approved by the ethics committee and have therefore been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments. We declare that all patients gave informed consent prior to inclusion in this study

Conflict of interest

MM is part of Siemens Speakers’ Bureau; ML is part of Siemens and Bayer Speakers’ Bureau, has grants from Siemens and Bayer and consults for Bracco;

MB is part of Siemens Speakers’ Bureau; MU is part of Siemens, Bayer, Bracco and Medtronic Speakers’ Bureau; and WW is part of Siemens Speakers’ Bureau.

No financial support for this study was received from any company listed above.

References

  1. 1.
    Lell MM, Wildberger JE, Alkadhi H, Damilakis J, Kachelriess M (2015) Evolution in computed tomography: the battle for speed and dose. Investig Radiol 50(9):629–644CrossRefGoogle Scholar
  2. 2.
    Raissaki M, Perisinakis K, Damilakis J, Gourtsoyiannis N (2010) Eye-lens bismuth shielding in paediatric head CT: artefact evaluation and reduction. Pediatr Radiol 40(11):1748–1754CrossRefPubMedGoogle Scholar
  3. 3.
    Brem MH, Zamani AA, Riva R et al (2007) Multidetector CT of the paranasal sinus: potential for radiation dose reduction. Radiology 243:847–852CrossRefPubMedGoogle Scholar
  4. 4.
    Hagtvedt T, Aalokken TM, Notthellen J, Kolbenstvedt A (2003) A new low-dose CT examination compared with standard-dose CT in the diagnosis of acute sinusitis. Eur Radiol 13:976–980PubMedGoogle Scholar
  5. 5.
    Hojreh A, Czerny C, Kainberger F (2005) Dose classification scheme for computed tomography of the paranasal sinuses. Eur J Radiol 56:31–37CrossRefPubMedGoogle Scholar
  6. 6.
    Lell MM, May MS, Brand M et al (2015) Imaging the parasinus region with a third-generation dual-source CT and the effect of tin filtration on image quality and radiation dose. AJNR Am J Neuroradiol 36(7):1225–1230CrossRefPubMedGoogle Scholar
  7. 7.
    Wuest W, May M, Saake M et al (2016) Low-dose CT of the paranasal sinuses: minimizing X-ray exposure with spectral shaping. Eur Radiol 26(11):4155–4161CrossRefPubMedGoogle Scholar
  8. 8.
    Buls N, Van Gompel G, Van Cauteren T et al (2015) Contrast agent and radiation dose reduction in abdominal CT by a combination of low tube voltage and advanced image reconstruction algorithms. Eur Radiol 25:1023–1031CrossRefPubMedGoogle Scholar
  9. 9.
    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
  10. 10.
    Landis JR, Koch GG (1977) The measurement of observer agreement for categorical data. Biometrics 33:159–174CrossRefPubMedGoogle Scholar
  11. 11.
    Hoxworth JM, Lal D, Fletcher GP et al (2014) Radiation dose reduction in paranasal sinus CT using model-based iterative reconstruction. AJNR Am J Neuroradiol 35(4):644–649CrossRefPubMedGoogle Scholar
  12. 12.
    Lell MM, May M, Deak P et al (2011) High-pitch spiral computed tomography: effect on image quality and radiation dose in pediatric chest computed tomography. Investig Radiol 46:116–123CrossRefGoogle Scholar
  13. 13.
    Bodelle B, Wichmann JL, Klotz N et al (2015) Seventy kilovolt ultra-low dose CT of the paranasal sinus: first clinical results. Clin Radiol 70(7):711–715CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Matthias S May
    • 1
  • Michael Brand
    • 1
  • Michael M Lell
    • 1
  • Martin Sedlmair
    • 2
  • Thomas Allmendinger
    • 2
  • Michael Uder
    • 1
  • Wolfgang Wuest
    • 1
    Email author
  1. 1.Department of RadiologyUniversity Hospital ErlangenErlangenGermany
  2. 2.Siemens Healthcare GmbHForchheimGermany

Personalised recommendations