Investigation of contrast-enhanced subtracted breast CT images with MAP-EM based on projection-based weighting imaging

  • Zhengdong Zhou
  • Shaolin Guan
  • Runchao Xin
  • Jianbo Li
Scientific Paper


Contrast-enhanced subtracted breast computer tomography (CESBCT) images acquired using energy-resolved photon counting detector can be helpful to enhance the visibility of breast tumors. In such technology, one challenge is the limited number of photons in each energy bin, thereby possibly leading to high noise in separate images from each energy bin, the projection-based weighted image, and the subtracted image. In conventional low-dose CT imaging, iterative image reconstruction provides a superior signal-to-noise compared with the filtered back projection (FBP) algorithm. In this paper, maximum a posteriori expectation maximization (MAP-EM) based on projection-based weighting imaging for reconstruction of CESBCT images acquired using an energy-resolving photon counting detector is proposed, and its performance was investigated in terms of contrast-to-noise ratio (CNR). The simulation study shows that MAP-EM based on projection-based weighting imaging can improve the CNR in CESBCT images by 117.7%–121.2% compared with FBP based on projection-based weighting imaging method. When compared with the energy-integrating imaging that uses the MAP-EM algorithm, projection-based weighting imaging that uses the MAP-EM algorithm can improve the CNR of CESBCT images by 10.5%–13.3%. In conclusion, MAP-EM based on projection-based weighting imaging shows significant improvement the CNR of the CESBCT image compared with FBP based on projection-based weighting imaging, and MAP-EM based on projection-based weighting imaging outperforms MAP-EM based on energy-integrating imaging for CESBCT imaging.


Photon counting detector Projection-based weighting Contrast-enhanced subtracted breast computer tomography (CESBCT) Maximum a posteriori expectation maximization algorithm 



This work was supported by the National Natural Science Foundation of China (No. 51575256), the Key Research and Development Plan (Social Development) of Jiangsu Province (No. BE2017730), the Key Industrial Research and Development Project of Chongqing, and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.


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Copyright information

© Australasian College of Physical Scientists and Engineers in Medicine 2018

Authors and Affiliations

  • Zhengdong Zhou
    • 1
  • Shaolin Guan
    • 1
    • 2
  • Runchao Xin
    • 1
    • 2
  • Jianbo Li
    • 1
    • 2
  1. 1.State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjingPeople’s Republic of China
  2. 2.Department of Nuclear Science and EngineeringNanjing University of Aeronautics and AstronauticsNanjingPeople’s Republic of China

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