Title :
Effect of intercrystal Compton scatter on efficiency and image noise in small animal PET module
Author :
Park, Sang-June ; Rogers, W.L. ; Clinthorne, Neal H.
Author_Institution :
Dept. of Nucl. Eng. & Radiol. Sci., Michigan Univ., Ann Arbor, MI, USA
Abstract :
The effect of intercrystal Compton scatter in a small animal PET module was investigated using electron-gamma shower code (EGS4) simulations. The size of detector module is fixed at a 16 mm×16 mm crystal array. Monte Carlo simulations were performed to estimate the effect of intercrystal scatter considering scintillation materials (BGO, LSO, and NaI), detector energy threshold, crystal size, and interaction position estimation methods on the fraction of correct coincidence efficiency (FCCE). Results show the crystal size (2 mm×2 mm×10 mm) currently used in MicroPET has the highest FCCE. In order to evaluate spatial resolution and image noise due to intercrystal scatter, the coincidence line response function (CLRF) of detector modules and 2D images using the MicroPET R4 geometry were reconstructed. The results demonstrate a very small effect on FWHM but considerable noise and contrast loss in images due to the tails of the CLRF resulting from intercrystal scatter.
Keywords :
Compton effect; Monte Carlo methods; image reconstruction; medical image processing; positron emission tomography; solid scintillation detectors; 10 mm; 2 mm; 2D images; BGO detector; LSO detector; MicroPET; MicroPET R4 geometry; Monte Carlo simulations; NaI detector energy threshold; coincidence line response function; contrast loss; crystal array; crystal size; detector modules; electron-gamma shower code simulations; fraction of correct coincidence efficiency; image noise; image reconstruction; interaction position estimation methods; intercrystal Compton scatter; scintillation materials; small animal PET module; spatial resolution; Animals; Crystalline materials; Geometry; Image reconstruction; Positron emission tomography; Scattering; Sensor arrays; Solid scintillation detectors; Spatial resolution; Tail;
Conference_Titel :
Nuclear Science Symposium Conference Record, 2003 IEEE
Print_ISBN :
0-7803-8257-9
DOI :
10.1109/NSSMIC.2003.1352351
