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Future Prospects of Spectral CT: Photon Counting

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Computed Tomography

Abstract

Dual-energy spectral CT has demonstrated numerous clinical benefits, yet there is potential to further improve the quantity and quality of acquired spectral data. Clinical dual-energy CT scanners are limited to two spectral measurements that overlap in spectral content. Photon-counting detectors use direct-conversion semiconductors, combined with pulse-height analysis electronics, to sort detected photons into energy bins. Photon-counting detectors can acquire more than two spectral measurements simultaneously, while also acquiring a nonspectral CT image. In addition to the spectral acquisition capabilities, photon-counting detectors have the additional benefits of higher spatial resolution and improved dose efficiency, compared to conventional CT detectors. This chapter explains the basic operation of photon-counting detectors and describes the potential benefits of photon-counting CT (PCCT), as well as the challenges of photon-counting technology. Examples are provided demonstrating the improved nonspectral CT images and new material decomposition applications made possible by PCCT.

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Acknowledgments

The author thanks David Cormode (University of Pennsylvania), Mats Danielsson (KTH Royal Institute of Technology and Prismatic Sensors), Cynthia McCollough (Mayo Clinic), Salim Si-Mohamed (Hospices Civils de Lyon), and Yoad Yagil (Philips Healthcare) for sharing images and information for this chapter.

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Authors and Affiliations

  1. Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, WI, USA

    Taly Gilat Schmidt

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  1. Taly Gilat Schmidt
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Correspondence to Taly Gilat Schmidt .

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Editors and Affiliations

  1. Department of Radiology, Duke University, Durham, NC, USA

    Ehsan Samei

  2. Department of Bioengineering and Radiology, Stanford University, Stanford, CA, USA

    Norbert J. Pelc

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Schmidt, T.G. (2020). Future Prospects of Spectral CT: Photon Counting. In: Samei, E., Pelc, N. (eds) Computed Tomography . Springer, Cham. https://doi.org/10.1007/978-3-030-26957-9_14

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  • DOI: https://doi.org/10.1007/978-3-030-26957-9_14

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  • Publisher Name: Springer, Cham

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  • Online ISBN: 978-3-030-26957-9

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