The impact of dual- and multi-energy CT on proton pencil beam range uncertainties: a Monte Carlo study.

The impact of dual- and multi-energy CT on proton pencil beam range uncertainties: a Monte Carlo study.
Phys Med Biol. 2018 Sep 05;:
Authors: Lalonde A, Simard M, Remy C, Bär E, Bouchard H
Abstract
The purpose of this work is to evaluate the impact of single-, dual-and multi-energy CT (SECT, DECT and MECT) on proton range uncertainties in a patient like geometry and a full Monte Carlo environment. A virtual patient is generated from a real patient pelvis CT scan, where known mass densities and elemental compositions are overwritten in each voxel. Simulated CT images for SECT, DECT and MECT are generated for two limiting cases: 1) theoretical and idealistic CT numbers only affected by Gaussian noise (case A, the best scenario) and 2) reconstructed polyenergetic sinograms containing beam hardening and reconstruction artifacts (case B, the worst scenario). Conversion of the simulated SECT images into Monte Carlo inputs is done following the stoichiometric calibration method. For DECT and MECT, the Bayesian eigentissue decomposition method of Lalonde et al. (2017) is used. Pencil beams from seven different angles around the virtual patient are simulated using TOPAS to assess the performance of each method. Percentage depth doses curves are compared to ground truth in order to determine the accuracy of range prediction of each imaging modality.
 For the idealistic images of case A, MECT and DECT slightly outperforms SECT. Root me...

Source: Physics in Medicine and Biology - September 5, 2018 Category: Physics Authors: Lalonde A, Simard M, Remy C, Bär E, Bouchard H Tags: Phys Med Biol Source Type: research