2016_Imaging for Physicists

Scatter Correction

 Most likely: Compton scattering  Compton equation = E

E

E

sc

(

) Ω −

1

cos 1

+

2 cm

0

l Relates photon energy before ( E ) and after scattering ( E sc ) to scattering angle Ω l m 0 c 2 : resting energy of electron before scattering

Correction strategies:

● Fitting scatter tails ● Direct measurement ● Dual energy window methods ● Multiple energy window methods ● Simulation-based methods

Spectral distribution of scattered 511 keV photons [2].

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ESTRO Teaching Course Advanced Imaging: PET – Reconstruction, Contouring