Annals of Nuclear Medicine

, Volume 28, Issue 6, pp 559–570 | Cite as

Derivation of attenuation map for attenuation correction of PET data in the presence of nanoparticulate contrast agents using spectral CT imaging

  • Hossein Ghadiri
  • Mohammad Bagher Shiran
  • Hamid Soltanian-Zadeh
  • Arman Rahmim
  • Habib Zaidi
  • Mohammad Reza AyEmail author
Original Article



Uptake value in quantitative PET imaging is biased due to the presence of CT contrast agents when using CT-based attenuation correction. Our aim was to examine spectral CT imaging to suppress inaccuracy of 511 keV attenuation map in the presence of multiple nanoparticulate contrast agents.


Using a simulation study we examined an image-based K-edge ratio method, in which two images acquired from energy windows located above and below the K-edge energy are divided by one another, to identify the exact location of all contrast agents. Multiple computerized phantom studies were conducted using a variety of NP contrast agents with different concentrations. The performance of the proposed methodology was compared to conventional single-kVp and dual-kVp methods using wide range of contrast agents with varying concentrations.


The results demonstrate that both single-kVp and dual-kVp energy mapping approaches produce inaccurate attenuation maps at 511 keV in the presence of multiple simultaneous contrast agents. In contrast, the proposed method is capable of handling multiple simultaneous contrast agents, thus allowing suppression of 511 keV attenuation map inaccuracy.


Attenuation map produced by spectral CT clearly outperforms conventional single-kVp and dual-kVp approaches in the generation of accurate attenuation maps in the presence of multiple contrast agents.


PET/CT Nanoparticulate contrast agents K-edge imaging Multi-energy spectral CT 



This work was supported by Tehran University of Medical Sciences under Grant 21342 and the Swiss National Science Foundation under grant SNSF 31003A-149957.


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Copyright information

© The Japanese Society of Nuclear Medicine 2014

Authors and Affiliations

  • Hossein Ghadiri
    • 1
    • 2
  • Mohammad Bagher Shiran
    • 3
  • Hamid Soltanian-Zadeh
    • 4
    • 5
  • Arman Rahmim
    • 6
  • Habib Zaidi
    • 7
    • 8
    • 9
  • Mohammad Reza Ay
    • 1
    • 2
    Email author
  1. 1.Department of Medical Physics and Biomedical EngineeringTehran University of Medical SciencesTehranIran
  2. 2.Research Center for Molecular and Cellular ImagingTehran University of Medical SciencesTehranIran
  3. 3.Department of Medical PhysicsIran University of Medical SciencesTehranIran
  4. 4.CIPCE, Department of Electrical and Computer EngineeringUniversity of TehranTehranIran
  5. 5.Department of RadiologyHenry Ford Health SystemDetroitUSA
  6. 6.Department of RadiologyJohns Hopkins UniversityBaltimoreUSA
  7. 7.Division of Nuclear MedicineGeneva University HospitalGenevaSwitzerland
  8. 8.Geneva Neuroscience CenterGeneva UniversityGenevaSwitzerland
  9. 9.Department of Nuclear Medicine and Molecular ImagingUniversity of Groningen, University Medical Center GroningenGroningenThe Netherlands

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