Maximum Likelihood Reconstruction for SPECT Using Monte Carlo Simulation

Reconstructed images for single photon emission computed tomography (SPECT) with quantitative compensation for scatter and attenuation are provided using Inverse Monte Carlo (IMOC): Maximum likelihood estimation with Monte Carlo modeling of the photon interaction and detection probabilities. Quantitative compensation was evaluated by comparing region of interest values for compensated images of line sources scanned in water with line sources scanned in air. Compensation was demonstrated for both 360° 180° acquisition. Lesion contrast was investigated for cold spheres in an active background.