Analytical construction of 3D NPS for a cone beam CT system

Jongduk Baek, Norbert J. Pelc

Research output: Chapter in Book/Report/Conference proceedingConference contribution

4 Citations (Scopus)

Abstract

Several experimental studies of the noise power spectrum (NPS) of cone-beam CT have been performed, but less attention has been paid to the analytical derivation of the 3D NPS. It is well known that noise in cone beam CT is nonstationary. When the image is reconstructed by using the FDK algorithm, different back-projection and cosine weightings are used for different reconstruction regions. In addition, the ray density and cone angle are also spatially dependent. As a result, a cone beam system has non-stationary noise. In order to characterize the noise behavior, we first construct the 3D NPS in a local reconstruction volume. Because cone beam rays passing through a small volume can be approximated as parallel rays, the 3D NPS of a small volume can be constructed by considering all effects. The 3D NPS of a large volume (which describes the average noise behavior but may not be valid throughout the volume) was generated by summing 3D NPS of small sub-volumes. The method was validated with computer simulations with uniform noise in the projection. 3D noise spectra of 3cm, 6cm, and 10 cm thick volumes were generated, and the radial NPS at different kz planes were compared with those of the analytically constructed 3D NPS. The results showed excellent matching for all cases. With the proposed method, non-stationary noise behavior of any local volume can be analyzed. The non-stationary noise behavior also causes a high-frequency roll-off in the NPS of a large volume, and as the volume size increases, the roll-off frequency decreases because the larger volume has more heterogeneous noise behavior.

Original languageEnglish
Title of host publicationMedical Imaging 2009
Subtitle of host publicationPhysics of Medical Imaging
DOIs
Publication statusPublished - 2009 Jun 15
EventMedical Imaging 2009: Physics of Medical Imaging - Lake Buena Vista, FL, United States
Duration: 2009 Feb 92009 Feb 12

Publication series

NameProgress in Biomedical Optics and Imaging - Proceedings of SPIE
Volume7258
ISSN (Print)1605-7422

Other

OtherMedical Imaging 2009: Physics of Medical Imaging
CountryUnited States
CityLake Buena Vista, FL
Period09/2/909/2/12

Fingerprint

Cone-Beam Computed Tomography
noise spectra
Power spectrum
Noise
power spectra
Cones
cones
rays
projection
Computer Simulation
derivation
computerized simulation
Computer simulation

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Atomic and Molecular Physics, and Optics
  • Radiology Nuclear Medicine and imaging

Cite this

Baek, J., & Pelc, N. J. (2009). Analytical construction of 3D NPS for a cone beam CT system. In Medical Imaging 2009: Physics of Medical Imaging [725805] (Progress in Biomedical Optics and Imaging - Proceedings of SPIE; Vol. 7258). https://doi.org/10.1117/12.813832
Baek, Jongduk ; Pelc, Norbert J. / Analytical construction of 3D NPS for a cone beam CT system. Medical Imaging 2009: Physics of Medical Imaging. 2009. (Progress in Biomedical Optics and Imaging - Proceedings of SPIE).
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Baek, J & Pelc, NJ 2009, Analytical construction of 3D NPS for a cone beam CT system. in Medical Imaging 2009: Physics of Medical Imaging., 725805, Progress in Biomedical Optics and Imaging - Proceedings of SPIE, vol. 7258, Medical Imaging 2009: Physics of Medical Imaging, Lake Buena Vista, FL, United States, 09/2/9. https://doi.org/10.1117/12.813832

Analytical construction of 3D NPS for a cone beam CT system. / Baek, Jongduk; Pelc, Norbert J.

Medical Imaging 2009: Physics of Medical Imaging. 2009. 725805 (Progress in Biomedical Optics and Imaging - Proceedings of SPIE; Vol. 7258).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Baek J, Pelc NJ. Analytical construction of 3D NPS for a cone beam CT system. In Medical Imaging 2009: Physics of Medical Imaging. 2009. 725805. (Progress in Biomedical Optics and Imaging - Proceedings of SPIE). https://doi.org/10.1117/12.813832