2016_Imaging for Physicists

Random Correction

 Randoms: Correction Methods:  Tail Fitting ● Estimate random distribution in the object by fitting the tails outside the object  Estimation from Single Rates ● Direct determination from single rates N a ab ∝ ⋅ = τ 2 2

N NN R b a

and N b  Delayed Coincidence Channel Estimation ● Data stream containing signals from one channel is delayed for several times the coincidence window ● Removal of all annihilation events ● Any coincidences detected are random ● Subtraction from coincidences in the prompt channel

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ESTRO Teaching Course Advanced Imaging: PET – Reconstruction, Contouring