Dual-Energy Algorithms and Postprocessing Techniques

  • Cynthia H. McCollough
  • Bernhard Schmidt
  • Xin Liu
  • Lifeng Yu
  • Shuai Leng
Part of the Medical Radiology book series (MEDRAD)


Recently, dual energy CT has been routinely used in clinical practice for the applications of bone removal, kidney stone composition differentiation, gout identification, and generating virtual non-contrast images. This is mainly due to the material differentiation capability of dual energy CT in which patients are scanned with two distinguished beam energies. Processing algorithms used to obtain material-specific information were reviewed, including projection-based, image-based and hybrid methods. Pros and cons of each algorithm were compared. Different type of images generated from dual energy data sets (e.g. blended image, material-selective image and energy-selective image) were summarized and appropriate clinical applications were discussed. Finally, dose performance of dual energy CT, in comparison with single energy CT, was analyzed with the consideration of image quality.


Linear Attenuation Coefficient Mass Attenuation Coefficient Effective Atomic Number Blended Image Image Space Approach 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Cynthia H. McCollough
    • 1
  • Bernhard Schmidt
    • 2
  • Xin Liu
    • 1
  • Lifeng Yu
    • 1
  • Shuai Leng
    • 1
  1. 1.CT Clinical Innovation Center, Department of RadiologyOrganization Mayo ClinicRochesterUSA
  2. 2.Division Siemens HealthcareOrganization Computed Tomography CTE PAForchheimGermany

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