General...

Monte Carlo simulations are increasingly used in Nuclear Imaging to model imaging systems and to develop and assess tomographic reconstruction algorithms and correction methods for improved image quantification. Powerful computing systems and progress in parallelization techniques make them more and more efficient.

Monte Carlo simulation is performed using GATE simulation package. GATE (Geant4 Application for Tomographic Emission) is a generic Monte Carlo simulation platform based on a general purpose code GEANT4 and designed to answer the specific needs of PET/SPECT applications. In addition to the many potentialities provided by GEANT4, GATE includes specific modules necessary to perform realistic simulations including modules managing time and time-dependent processes (detector and source movements, radioactive decay, dynamic acquisitions), complex source distributions and easy description of scanner geometry.

Currently we investigate the use of GATE, in combination with realistic anthropomorphic phantoms (NCAT, Zubal) or small animal phantoms (MOBY), in order to simulate clinical trials or small animal experiments.  ΝCAT anthropomorphic phantom Clinical and simulated images: (up) tumor in lungs region; (down)heart imaging Clinical and simulated images of a brain tumor In addition we are using GATE to simulate prototype and clinical systems, as well as model physical phenomena to generated data for testing image reconstruction, attenuation correction and scatter correctcion algorithms.