Using Monte Carlo based system matrix for increasing detection efficiency in small animal SPECT

We have shown that when using a pinhole SPECT and reconstructing images using a Monte Carlo based system matrix, it is possible to increase the aperture of the pinhole diameter by a factor of 3 going from 0.5 mm to 1.5 mm, increasing so the detection efficiency of the system by a factor of 6 and this without degrading the spatial resolution of the reconstructed images. In future, we will study the limit of the pinhole aperture diameter that can be used in combination with a Monte Carlo based system matrix leading to an increase in the detection efficiency of the system and conserving the spatial resolution in the reconstructed images.