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Quantitative analysis of a reconstruction method for fully three-dimensional PET.

J Suckling·R J Ott·B J Deehan
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Abstract

The major advantage of positron emission tomography (PET) using large area planar detectors over scintillator-based commercial ring systems is the potentially larger (by a factor of two or three) axial field-of-view (FOV). However, to achieve the space invariance of the point spread function necessary for Fourier filtering a polar angle rejection criterion is applied to the data during backprojection resulting in a trade-off between FOV size and sensitivity. A new algorithm due to Defrise and co-workers developed for list-mode data overcomes this problem with a solution involving the division of the image into several subregions. A comparison between the existing backprojection-then-filter algorithm and the new method (with three subregions) has been made using both simulated and real data collected from the MUP-PET positron camera. Signal-to-noise analysis reveals that improvements of up to a factor of 1.4 are possible resulting from an increased data usage of up to a factor of 2.5 depending on the axial extent of the imaged object. Quantitation is also improved.

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AlgorithmsHumansImage Processing, Computer-AssistedKidneyModels, StructuralMonte Carlo MethodTomography, Emission-ComputedComparative StudyJournal Article

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BibTeXRIS

J Suckling, R J Ott, B J Deehan. 1992. Quantitative analysis of a reconstruction method for fully three-dimensional PET.. https://doi.org/10.1088/0031-9155%2F37%2F3%2F018

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