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Scatter Fraction
Fraction of the total coincidences recorded in the
photopeak window that have been scattered
Sources of scattering
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Scattering within the object containing the radionuclide
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Scattering off the gantry components (lead septa/side shields)
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Scattering within the detectors
Scatter fraction can be reduced by
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TOF
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Usage of a powerful iterative reconstruction method
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Shielding of scattered photons by septa and endshiels
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Small coincidence window
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Good energy resolution
ESTRO Teaching Course Advanced Imaging: PET – Basic Principles
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