Artifact Mitigation in High Energy CT via Monte Carlo Simulation

摘要

The high energy (< 15MeV) incident polychromatic 7-ray spectrum and energy-resolved photon attenuations in steel, obtained via EGS/BEAM Monte Carlo, were applied to derive beam hardening correction in steel cylinders and pipes. Monte Carlo simulated pencil beam projections were processed using latch bit filters to isolate exiting primary photons. The beam hardening correction was applied to these projections, which were then interpolated to a uniform grid. Filtered back projections of the raysums with and without the beam hardening correction were compared. It was demonstrated that beam hardening artifacts can be successfully removed for steel structures.