SPECT dual-energy-window Compton correction : Scatter multiplier required for quantification

摘要: The dual-energy window Compton-scattering correction technique is defined here especially for accurate quantification of focal regions having higher than average uptake. relative to a known-activity reference source. scatter multiplier ("k" value) determined radioactive 99mTc sphere on or off the axis cylinder containing water with without background. Both maximum likelihood and filtered-backprojection reconstruction are employed. Either projections tomograms corrected. With tight interest, there tendency requisite "k" value be slightly lower as diameter increased. Neither location nor background perturbs "k", however, so constant good, first approximation. Then two-sphere validation test yields an accuracy 8% subtracted-tomograms = 1.30) 2% subtracted-projections 1.20). reference-source region interest which four times larger, reduced also now depends Although equivalent quantitatively, preferable filtered backprojection Chang attenuation since it produces less-noisy image.