Adaptive noise correction of dual-energy computed tomography images

  • Rafael Simon Maia
  • Christian Jacob
  • Amy K. Hara
  • Alvin C. Silva
  • William Pavlicek
  • J. Ross Mitchell
Original Article



Noise reduction in material density images is a necessary preprocessing step for the correct interpretation of dual-energy computed tomography (DECT) images. In this paper we describe a new method based on a local adaptive processing to reduce noise in DECT images


An adaptive neighborhood Wiener (ANW) filter was implemented and customized to use local characteristics of material density images. The ANW filter employs a three-level wavelet approach, combined with the application of an anisotropic diffusion filter. Material density images and virtual monochromatic images are noise corrected with two resulting noise maps.


The algorithm was applied and quantitatively evaluated in a set of 36 images. From that set of images, three are shown here, and nine more are shown in the online supplementary material. Processed images had higher signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) than the raw material density images. The average improvements in SNR and CNR for the material density images were 56.5 and 54.75 %, respectively.


We developed a new DECT noise reduction algorithm. We demonstrate throughout a series of quantitative analyses that the algorithm improves the quality of material density images and virtual monochromatic images.


Material density Dual-energy computed tomography Noise reduction Adaptive Wiener filter 


Compliance with ethical standards

Conflicts of interest

Rafael Simon Maia, Christian Jacob, Amy K. Hara, Alvin C. Silva, William Pavlicek and J.Ross Mitchell declare that they have no conflict of interest.

Supplementary material

11548_2015_1297_MOESM1_ESM.pdf (32.3 mb)
Supplementary material 1 (pdf 33092 KB)


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Copyright information

© CARS 2015

Authors and Affiliations

  • Rafael Simon Maia
    • 1
  • Christian Jacob
    • 1
  • Amy K. Hara
    • 2
  • Alvin C. Silva
    • 2
  • William Pavlicek
    • 2
  • J. Ross Mitchell
    • 2
  1. 1.Department of Computer ScienceUniversity of CalgaryCalgaryCanada
  2. 2.Department of RadiologyMayo ClinicScottsdaleUSA

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