Monte Carlo simulation of X-ray grating interferometry systems

Sketch of a GI simulation setup with flat gratings. The aim of the algorithm is to simultaneously estimate quantities related scattering and interference.

Simulations can aid the development process of clinical and non-clinical applications of X-ray grating interferometry (GI) with the estimation of patient and imaging relevant quantities like dose, spectra, image quality or visibility. Current state of the art simulation frameworks can either simulate interference patterns in case of wave propagation or scattering effects in the case of Monte Carlo.  Even though, the potential of MC techniques to simulate interference patterns in GI setups has been demonstrated on smaller scales, there is no standard simulation framework capable of simultaneously including interference and scattering effects occurring in the imaging process of a clinical GI application.

Based on quantum mechanics a new GI Monte Carlo simulation framework for GI setups is developed in this work, with the aim to simulate scattering and interference phenomena within one framework. After a proof of principle on smaller scales with flat gratings, the algorithm will be extended for the simulation of clinically relevant volumes and extended to bent gratings. The use of Monte Carlo techniques opens additional opportunities for the simulation of GI devices like the use of incoherent sources, dose estimation or the impact of setup errors on performance.

References
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Collaboration
  • Division of Medical Radiation Physics and Department of Radiation Oncology at Inselspital in Bern
Contact
Stefan Tessarini, stefan.tessarini@psi.ch+41 56 310 29 68