Monte Carlo simulation of cone-beam X-ray computer tomography projection

A Monte Carlo simulation method of cone-beam X-ray computer tomography (X-CT) projection is presented. X-ray photons are sampled in series and traced with random discrete steps. Projection signals are obtained from deposited energy in the detector zone. Simulations in accordance with imaging physics are generated by adopting the Monte Carlo toolkit EGSnrc, which is batch-programmed for background calculation. In contrast with the commonly used default settings, acceleration investigation and parameters optimization lead to a decreasing in simulation time around 100 times. As expected, beam-hardening and scattering artifacts are revealed in the images reconstructed from the simulated projection. The method is convenient for further developing and can be the basis of researches in the scatter correction upon cone-beam X-CT prototype. Compared with the data measured from real machines, this method is validated with 1.18% error.