Limits...
SVD-based evaluation of multiplexing in multipinhole SPECT systems.

Jorgensen AK, Zeng GL - Int J Biomed Imaging (2008)

Bottom Line: This figure of merit contains significantly more information than the condition number of the system, and is therefore more revealing of system performance.The proposed figure of merit is useful for predicting system performance, but additional steps could be taken to improve its accuracy and applicability.The limits of the proposed method are discussed, and possible improvements to it are proposed.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA. aaron.jorgensen@utah.edu

ABSTRACT
Multipinhole SPECT system design is largely a trial-and-error process. General principles can give system designers a general idea of how a system with certain characteristics will perform. However, the specific performance of any particular system is unknown before the system is tested. The development of an objective evaluation method that is not based on experimentation would facilitate the optimization of multipinhole systems. We derive a figure of merit for prediction of SPECT system performance based on the entire singular value spectrum of the system. This figure of merit contains significantly more information than the condition number of the system, and is therefore more revealing of system performance. This figure is then compared with simulated results of several SPECT systems and is shown to correlate well to the results of the simulations. The proposed figure of merit is useful for predicting system performance, but additional steps could be taken to improve its accuracy and applicability. The limits of the proposed method are discussed, and possible improvements to it are proposed.

No MeSH data available.


Apertures used in final simulation.
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fig3: Apertures used in final simulation.

Mentions: Final simulations were run for a three-dimensional phantom with atwo-dimensional detector. The phantomused (Figure 2) is a custom 64 × 64 × 64 voxel phantom, which has been made toresemble the Shepp-Logan phantom. The Shepp-Logan phantom is used frequently inanalysis of medical imaging systems, and is designed to resemble a head. The phantom was imaged at 60 angles to a 128-by-128pixel detector through apertures with varying numbers of holes and varyingarrangements of holes. The apertures areillustrated in Figures 3(a)–3(f), and will be referred to as apertures A through F, respectively. Poisson noisewas added to these projections.


SVD-based evaluation of multiplexing in multipinhole SPECT systems.

Jorgensen AK, Zeng GL - Int J Biomed Imaging (2008)

Apertures used in final simulation.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2605944&req=5

fig3: Apertures used in final simulation.
Mentions: Final simulations were run for a three-dimensional phantom with atwo-dimensional detector. The phantomused (Figure 2) is a custom 64 × 64 × 64 voxel phantom, which has been made toresemble the Shepp-Logan phantom. The Shepp-Logan phantom is used frequently inanalysis of medical imaging systems, and is designed to resemble a head. The phantom was imaged at 60 angles to a 128-by-128pixel detector through apertures with varying numbers of holes and varyingarrangements of holes. The apertures areillustrated in Figures 3(a)–3(f), and will be referred to as apertures A through F, respectively. Poisson noisewas added to these projections.

Bottom Line: This figure of merit contains significantly more information than the condition number of the system, and is therefore more revealing of system performance.The proposed figure of merit is useful for predicting system performance, but additional steps could be taken to improve its accuracy and applicability.The limits of the proposed method are discussed, and possible improvements to it are proposed.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT 84112, USA. aaron.jorgensen@utah.edu

ABSTRACT
Multipinhole SPECT system design is largely a trial-and-error process. General principles can give system designers a general idea of how a system with certain characteristics will perform. However, the specific performance of any particular system is unknown before the system is tested. The development of an objective evaluation method that is not based on experimentation would facilitate the optimization of multipinhole systems. We derive a figure of merit for prediction of SPECT system performance based on the entire singular value spectrum of the system. This figure of merit contains significantly more information than the condition number of the system, and is therefore more revealing of system performance. This figure is then compared with simulated results of several SPECT systems and is shown to correlate well to the results of the simulations. The proposed figure of merit is useful for predicting system performance, but additional steps could be taken to improve its accuracy and applicability. The limits of the proposed method are discussed, and possible improvements to it are proposed.

No MeSH data available.