Model mismatch and the ideal observer in SPECT

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

Abstract

SPECT acquisition parameters can be optimized using the Ideal Observer (IO) applied to projections. The IO implicitly has perfect knowledge of the image formation process, and thus its performance reflects the best achievable with perfect compensation. However, SPECT images are often reconstructed with imperfect or no compensation. This mismatch between the reconstruction and IO can give rise to suboptimal performance when human observers interpret SPECT images. In this study, we investigated the importance of including 'model mismatch' (MM) in the IO in the context of myocardial perfusion SPECT for a signal known exactly/background known statistically (SKE/BKS) task. We optimized the energy window using the IO with and without MM. We evaluated IO performance when the observer had (1) a perfect and (2) no or (3) an approximate model of scatter. We used an anthropomorphic model observer (AO) as a benchmark for human observer performance and compared optimal energy windows. IO performance was relatively insensitive to energy window settings for case 1. Performance for case 2 was significantly worse than for 1, and the optimal window width was 13-15%. For case 3, performance was similar to case 1. Performance for the AO was similar to cases 2 and 3 when scatter compensation was or was not, respectively, included in the reconstruction. Incorporating MM into the IO is a new approach for improving agreement of the IO with human observers. This allows optimization of acquisition and instrumentation parameters in the presence of non-ideal compensation methods more efficiently than reconstructed-image-domain AOs.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
Volume8673
DOIs
StatePublished - 2013
EventSPIE Medical Imaging Symposium 2013: Image Perception, Observer Performance, and Technology Assessment - Lake Buena Vista, FL, United States
Duration: Feb 10 2013Feb 11 2013

Other

OtherSPIE Medical Imaging Symposium 2013: Image Perception, Observer Performance, and Technology Assessment
CountryUnited States
CityLake Buena Vista, FL
Period2/10/132/11/13

Fingerprint

SPECT
Observer
acquisition
Model
human performance
Scatter
Image processing
energy
projection
Energy
Compensation and Redress
optimization
Human Performance
Approximate Model

Keywords

  • Anthropomorphic observer and SPECT
  • Model mismatch
  • The ideal observer

ASJC Scopus subject areas

  • Applied Mathematics
  • Computer Science Applications
  • Electrical and Electronic Engineering
  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Ghaly, M., Links, J. M., Du, Y., & Frey, E. (2013). Model mismatch and the ideal observer in SPECT. In Proceedings of SPIE - The International Society for Optical Engineering (Vol. 8673). [86730K] https://doi.org/10.1117/12.2007529

Model mismatch and the ideal observer in SPECT. / Ghaly, Mickel; Links, Jonathan M; Du, Yong; Frey, Eric.

Proceedings of SPIE - The International Society for Optical Engineering. Vol. 8673 2013. 86730K.

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

Ghaly, M, Links, JM, Du, Y & Frey, E 2013, Model mismatch and the ideal observer in SPECT. in Proceedings of SPIE - The International Society for Optical Engineering. vol. 8673, 86730K, SPIE Medical Imaging Symposium 2013: Image Perception, Observer Performance, and Technology Assessment, Lake Buena Vista, FL, United States, 2/10/13. https://doi.org/10.1117/12.2007529
Ghaly M, Links JM, Du Y, Frey E. Model mismatch and the ideal observer in SPECT. In Proceedings of SPIE - The International Society for Optical Engineering. Vol. 8673. 2013. 86730K https://doi.org/10.1117/12.2007529
Ghaly, Mickel ; Links, Jonathan M ; Du, Yong ; Frey, Eric. / Model mismatch and the ideal observer in SPECT. Proceedings of SPIE - The International Society for Optical Engineering. Vol. 8673 2013.
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