A 3-D Monte Carlo simulation of a small animal positron emission tomograph with millimeter spatial resolution

The authors have used the EGS4 Monte Carlo code to simulate the performance of a Positron Emission Tomograph for small animals. The tomograph is a four-head detector, made of matrices of 400 YAP:Ce finger-like crystals (2/spl times/2/spl times/30 mm/sup 3/ each) coupled to Position Sensitive Photo-Multipliers (Hamamatsu R2486-06). 3-D reconstruction algorithms have been applied to the 3-D simulated data. The Monte Carlo results show that a spatial resolution below 2 mm (FWHM) can be obtained over a field of view of 2/spl times/2/spl times/2 cm with a sensitivity of about 550 counts/(/spl mu/Cis) for a gantry diameter of 15 cm, and a threshold of 150 keV.