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Approaches, advantages, and challenges to photon counting detector and multi-energy CT

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Abstract

Photon counting detector CT (PCD-CT) is the newest major development in CT technology and has been commercially available since 2021. It offers major technological advantages over current standard-of-care energy integrating detector CT (EID-CT) including improved spatial resolution, improved iodine contrast to noise ratio, multi-energy imaging, and reduced noise. This article serves as a foundational basis to the technical approaches and concepts of PCD-CT technology with primary emphasis on detector technology in direct comparison to EID-CT. The article also addresses current technological challenges to PCD-CT with particular attention to cross talk and its causes (e.g., Compton scattering, fluorescence, charge sharing, K-escape) as well as pile-up.

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Acknowledgements

The authors would like to thank the working members of the Society of Abdominal Radiology Photon Counting CT Emerging Technology Commission for reviewing and endorsing this work for publication.

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Authors and Affiliations

  1. Departments of Radiology and Medical Physics, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA

    Giuseppe V. Toia & Guang-Hong Chen

  2. Department of Radiology, University of Washington, Seattle, WA, USA

    Achille Mileto

  3. Department of Radiology, Northwestern University, Chicago, IL, USA

    Amir A. Borhani

  4. Department of Radiology, UT Southwestern Medical Center, Dallas, TX, USA

    Liqiang Ren

  5. Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA

    Jennifer W. Uyeda

  6. Department of Radiology, Duke University Health System, Durham, NC, USA

    Daniele Marin

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All authors have reviewed and approved the final document and provided editorial input and met all ICJME requirements for authorship.

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Correspondence to Giuseppe V. Toia.

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Competing interests

Giuseppe V. Toia is an independent consultant for GE Healthcare and Canon Medical on work unrelated to this manuscript. Achille Mileto has no disclosures. Amir A. Borhani receives in-kind research support from Siemens Healthineers and is also consultant to Boston Scientific and AstraZeneca for works unrelated to this manuscript. Guang-Hong Chen receives research support from GE Healthcare for work unrelated to this manuscript and research support from National Institutes of Health for work unrelated to this manuscript. Liqiang Ren has no disclosures. Jennifer W. Uyeda has no disclosures. Daniele Marin receives research support from Siemens Healthineers for work unrelated to this manuscript.

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Toia, G.V., Mileto, A., Borhani, A.A. et al. Approaches, advantages, and challenges to photon counting detector and multi-energy CT. Abdom Radiol (2024). https://doi.org/10.1007/s00261-024-04357-x

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