Modeling high energy (I-131) pinhole collimator for small animal gamma ray imaging device by Monte Carlo simulation (GATE 6.0)

We investigated optimized collimator designs for I-131 high energy gamma ray imaging on small animal gamma camera. The simulated structures of the pinhole collimator were evaluated by sensitivity, true, scatter and penetration count rates, and spatial resolution. The parameters, which were pinhole diameter, acceptance angle, and aperture thickness, were determined to improve image resolution with geometric conditions. In this study we showed optimized pinhole design for high energy I-131 imaging to meet the tradeoff between sensitivity and resolution..