Cascaded systems analysis of the 3D NEQ for cone-beam CT and tomosynthesis

D. J. Tward, J. H. Siewerdsen, R. A. Fahrig, A. R. Pineda

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

20 Scopus citations


Crucial to understanding the factors that govern imaging performance is a rigorous analysis of signal and noise transfer characteristics (e.g., MTF, NPS, and NEQ) applied to a task-based performance metric (e.g., detectability index). This paper advances a theoretical framework for calculation of the NPS, NEQ, and DQE of cone-beam CT (CBCT) and tomosynthesis based on cascaded systems analysis. The model considers the 2D projection NPS propagated through a series of reconstruction stages to yield the 3D NPS, revealing a continuum (from 2D projection radiography to limitedangle tomosynthesis and fully 3D CBCT) for which NEQ and detectability index may be investigated as a function of any system parameter. Factors considered in the cascade include: system geometry; angular extent of source-detector orbit; finite number of views; log-scaling; application of ramp, apodization, and interpolation filters; back-projection; and 3D noise aliasing - all of which have a direct impact on the 3D NEQ and DQE. Calculations of the 3D NPS were found to agree with experimental measurements across a broad range of imaging conditions. The model presents a theoretical framework that unifies 3D Fourier-based performance metrology in tomosynthesis and CBCT, providing a guide to optimization that rigorously considers the system configuration, reconstruction parameters, and imaging task.

Original languageEnglish (US)
Title of host publicationMedical Imaging 2008 - Physics of Medical Imaging
StatePublished - May 14 2008
Externally publishedYes
EventMedical Imaging 2008 - Physics of Medical Imaging - San Diego, CA, United States
Duration: Feb 18 2008Feb 21 2008

Publication series

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


OtherMedical Imaging 2008 - Physics of Medical Imaging
Country/TerritoryUnited States
CitySan Diego, CA


  • 3D imaging, imaging performance
  • Cascaded systems analysis
  • Cone-beam CT
  • Flat-panel detector
  • NEQ
  • NPS
  • Noise-equivalent quanta
  • Noise-power spectrum
  • Tomosynthesis

ASJC Scopus subject areas

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


Dive into the research topics of 'Cascaded systems analysis of the 3D NEQ for cone-beam CT and tomosynthesis'. Together they form a unique fingerprint.

Cite this