The role of Monte Carlo simulation in understanding the performance of proton computed tomography

Abstract

Proton computed tomography (pCT) is a promising tomographic imaging modality allowing direct reconstruction of proton relative stopping power (RSP) required for proton therapy dose calculation. In this review article, we aim at highlighting the role of Monte Carlo (MC) simulation in pCT studies. After describing the requirements for performing proton computed tomography and the various pCT scanners actively used in recent research projects, we present an overview of available MC simulation platforms. The use of MC simulations in the scope of investigations of image reconstruction, and for the evaluation of optimal RSP accuracy, precision and spatial resolution omitting detector effects is then described. In the final sections of the review article, we present specific applications of realistic Monte Carlo simulations of an existing pCT scanner prototype, which we describe in detail.

Comparative accuracy and resolution assessment of two prototype proton computed tomography scanners

“…To generate WEPL measurements from the ADC readout, the phase-II scanner makes use of an elaborate calibration procedure based on data from a double-wedged polystyrene phantom (RSP= 1.03) complemented by one to four rectangular polystyrene blocks. 50 A detailed description of the calibration procedure is given in several previous publications, including Bashkirov et al, 45 Piersimoni et al, 50 Dedes et al, 51 and Schultze et al 49 The calibration runs cover the complete WEPL range of the detector. They are used to establish twodimensional histograms binned by WEPL and energy deposit to the stopping stage.…”

Monte Carlo methods for device simulations in radiation therapy

“…Arbor et al simulated a pCT scanner with the GATE v6 code and found an advantage in range estimation for a proton beam in a patient body as compared to estimates based on x-ray CT (Arbor et al 2015). Recently, Dedes et al summarized the role of MCSs and MC platforms for pCT scanners including geometry, physics, scoring information in pCT developments for functionalities required for pCT scanners (Dedes et al 2020). They proposed that Geant4 and FLUKA are the main particle transport frameworks being used for pCT imaging.…”

A Geant4 simulation of X-ray emission for three-dimensional proton imaging of microscopic samples

“…Although since the 1980's the main application areas of STIM and PIXE tomography have been in microscopy, in recent years the growing number of medical proton accelerators for cancer therapy worldwide, has raised a new interest for these techniques in medical imaging. In cancer treatment, proton CT has been largely developed to improve the accuracy of dose calculation for proton treatment planning and also for pre-treatment verification of patient positioning [7]. With regard to PIXE tomography, its potential application for small animal and medical imaging was first demonstrated on test samples of a few centimeters in size, at the proton therapy center of Hokkaido University Hospital, Japan [8].…”