2017 Imaging for Physicists Coursebook
Performance of PET Systems: Count Rate Performance
Ratio Trues/Randoms unbalanced for high Activities Processing of detected photons takes finite time Noise Equivalent Count Rate: T 2
T : trues S : scattered R : randoms f : rel. area of object on proj. surface
NECR
2
fR ST
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
Maximum image quality
Low image contrast
using a 11 C-filled cylinder in water.
Noisy image
26
ESTRO Teaching Course Advanced Imaging: PET – Basic Principles
Made with FlippingBook - Online catalogs