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PubMed · 6982965

Attenuation compensation in single-photon emission tomography: a comparative evaluation.

M H Lewis·J T Willerson·S E Lewis·F J Bonte·R W Parkey·E M Stokely
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Abstract

Attenuation of photons in single-photon emission tomography (SPECT) makes three-dimensional reconstruction of unknown radioactivity distributions a mathematically intractable problem. Approaches to approximate SPECT reconstruction range from ignoring the effect of photon attenuation to incorporating assumed attenuation coefficients into an iterative reconstruction procedure. We have developed a computer-based simulation method to assess the relative effectiveness of attenuation compensation procedures. The method was used to study four procedures for myocardial SPECT using an infarct-avid radiopharmaceutical, Tc-99m stannous pyrophosphate. Reconstructions were evaluated by two criteria: overall (sum-of-squares) accuracy, and accuracy of lesion sizing. For moderate- to high-contrast studies there were no significant differences among the reconstructions by either evaluation criterion; for low contrast ratios the iterative method produced lower sum-of-squares criterion; for low contrast ratios the iterative method produced lower sum-of-squares error. We conclude that the additional expense of the iterative method is not justified under the conditions of this study. The approach used here is a convenient tool for evaluating specific SPECT reconstruction alternatives.

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HumansMathematicsModels, StructuralMyocardial InfarctionTechnetiumTechnetium Tc 99m PyrophosphateTin PolyphosphatesTomography, Emission-ComputedComparative StudyJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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M H Lewis, J T Willerson, S E Lewis, F J Bonte, R W Parkey, E M Stokely. 1982. Attenuation compensation in single-photon emission tomography: a comparative evaluation.. https://pubmed.ncbi.nlm.nih.gov/6982965/

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