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Model-based scatter correction for fully 3D PET.

J M Ollinger
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Abstract

A method is presented that directly calculates the mean number of scattered coincidences in data acquired with fully 3D positron emission tomography (PET). This method uses a transmission scan, an emission scan, the physics of Compton scatter, and a mathematical model of the scanner in a forward calculation of the number of events for which one photon has undergone a single Compton interaction. The distribution of events for which multiple Compton interactions have occurred is modelled as a linear transformation of the single-scatter distribution. Computational efficiency is achieved by sampling at rates no higher than those required by the scatter distribution and by implementing the algorithm using look-up tables. Evaluation studies in phantoms with large scatter fractions show that the method yields images with quantitative accuracy equivalent to that of slice-collimated PET in clinically useful times.

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AlgorithmsHumansModels, TheoreticalMonte Carlo MethodPhantoms, ImagingReproducibility of ResultsScattering, RadiationSensitivity and SpecificityTomography, Emission-ComputedJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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J M Ollinger. 1996. Model-based scatter correction for fully 3D PET.. https://doi.org/10.1088/0031-9155%2F41%2F1%2F012

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