2017 Imaging for Physicists Coursebook

Prompt Events (II)

 Scattered events ●

One or both photons detected have undergone a Compton interaction Loss in energy and change in direction

● ●

Due to poor energy resolution, many scattered photons cannot be discriminated ● Wrong LOR assigned  Multiple (triple) events ● Three events from two annihilations detected ● Event is disregarded ● Proportional to count rate

22

ESTRO Teaching Course Advanced Imaging: PET – Basic Principles