Korean Journal of Radiology

The Korean Society of Radiology (대한영상의학회)
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Spectral Computed Tomography: Fundamental Principles and Recent Developments

  • Aaron So (Imaging Program, Lawson Health Research Institute) ;
  • Savvas Nicolaou (Department of Emergency and Trauma Imaging, Vancouver General Hospital)
  • Received : 2020.02.19
  • Accepted : 2020.04.13
  • Published : 2021.01.01
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Abstract

CT is a diagnostic tool with many clinical applications. The CT voxel intensity is related to the magnitude of X-ray attenuation, which is not unique to a given material. Substances with different chemical compositions can be represented by similar voxel intensities, making the classification of different tissue types challenging. Compared to the conventional single-energy CT, spectral CT is an emerging technology offering superior material differentiation, which is achieved using the energy dependence of X-ray attenuation in any material. A specific form of spectral CT is dual-energy imaging, in which an additional X-ray attenuation measurement is obtained at a second X-ray energy. Dual-energy CT has been implemented in clinical settings with great success. This paper reviews the theoretical basis and practical implementation of spectral/dual-energy CT.

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