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Iterative reconstruction techniques for computed tomography Part 1: Technical principles

  • Computed Tomography
  • Published:
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Abstract

Objectives

To explain the technical principles of and differences between commercially available iterative reconstruction (IR) algorithms for computed tomography (CT) in non-mathematical terms for radiologists and clinicians.

Methods

Technical details of the different proprietary IR techniques were distilled from available scientific articles and manufacturers' white papers and were verified by the manufacturers. Clinical results were obtained from a literature search spanning January 2006 to January 2012, including only original research papers concerning IR for CT.

Results

IR for CT iteratively reduces noise and artefacts in either image space or raw data, or both. Reported dose reductions ranged from 23 % to 76 % compared to locally used default filtered back-projection (FBP) settings, with similar noise, artefacts, subjective, and objective image quality.

Conclusion

IR has the potential to allow reducing the radiation dose while preserving image quality. Disadvantages of IR include blotchy image appearance and longer computational time. Future studies need to address differences between IR algorithms for clinical low-dose CT.

Key Points

• Iterative reconstruction technology for CT is presented in non-mathematical terms.

• IR reduces noise and artefacts compared to filtered back-projection.

• IR can improve image quality in routine-dose CT and lower the radiation dose.

• IR's disadvantages include longer computation and blotchy appearance of some images.

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Abbreviations

AIDR 3D:

Adaptive Iterative Dose Reduction 3D

ART:

Algebraic reconstruction technique

ASIR:

Adaptive Statistical Iterative Reconstruction

CNR:

Contrast-to-noise ratio

CT:

Computed tomography

CTDIvol :

Volume Computed Tomography Dose Index

DLP:

Dose-length product

FBP:

Filtered back-projection

IRIS:

Iterative Reconstruction in Image Space

MBIR:

Model-Based Iterative Reconstruction

SAFIRE:

Sinogram-Affirmed Iterative Reconstruction

SNR:

Signal-to-noise ratio

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Acknowledgements

We would like to thank Roy Irwan, PhD (Toshiba Medical Systems), Alain Vlassenbroek, PhD (Philips Healthcare), Raymond Ubaghs (GE Healthcare), and Michiel de Bruijn (Siemens Medical Solutions) for reviewing the IR algorithm paragraphs.

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Authors and Affiliations

  1. Department of Radiology, Utrecht University Medical Center, P.O. Box 85500, E01.132, 3508 GA, Utrecht, The Netherlands

    Martin J. Willemink, Pim A. de Jong, Tim Leiner, Rutger A. J. Nievelstein, Ricardo P. J. Budde & Arnold M. R. Schilham

  2. Cardiothoracic Surgery, Utrecht University Medical Center, Utrecht, The Netherlands

    Linda M. de Heer

  3. Department of Radiology, Gelre Hospital, Apeldoorn, The Netherlands

    Ricardo P. J. Budde

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  1. Martin J. Willemink
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  2. Pim A. de Jong
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Correspondence to Martin J. Willemink.

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Willemink, M.J., de Jong, P.A., Leiner, T. et al. Iterative reconstruction techniques for computed tomography Part 1: Technical principles. Eur Radiol 23, 1623–1631 (2013). https://doi.org/10.1007/s00330-012-2765-y

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