2016_Imaging for Physicists

Count Rate Performance  Ratio Trues/Randoms unbalanced for high Activities  Processing of detected photons takes finite time  Noise Equivalent Count Rate: fR ST T NECR 2 2   T : trues

S : scattered R : randoms f : rel. area of object on proj. surface

Count rate curves for true, random and multiple coincidences. Derived curves for expected and noise equivalent count rate [2]. Data recorded on a CTI ECAT 953B PET using a 11 C-filled cylinder in water.

Maximum image quality

Low image contrast

Noisy image

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ESTRO Teaching Course Advanced Imaging: PET – Basic Principles