SUET553: Monte Carlo Calculation of Proton Bragg Peak Displacements in the Presence of Al2O3:C Dosimeters
Abstract
Purpose: The application of optically stimulated luminescence dosimeters (OSLDs) may be extended to clinical investigations verifying irradiated doses in small animal models. In proton beams, the accurate positioning of the Bragg peak is essential for tumor targeting. The purpose of this study was to estimate the displacement of a pristine Bragg peak when an Al2O3:C nanodot (Landauer, Inc.) is placed on the surface of a water phantom and to evaluate corresponding changes in dose. Methods: Clinical proton pencil beam simulations were carried out with using TOPAS, a Monte Carlo platform layered on top of GEANT4. Pointshaped beams with no energy spread were modeled for energies 100MV, 150MV, 200MV, and 250MV. Dose scoring for 100,000 particle histories was conducted within a water phantom (20cm × 20cm irradiated area, 40cm depth) with its surface placed 214.5cm away from the source. The modeled nanodot had a 4mm radius and 0.2mm thickness. Results: A comparative analysis of Monte Carlo depth dose profiles modeled for these proton pencil beams did not demonstrate an energy dependent in the Bragg peak shift. The shifts in Bragg Peak depth for water phantoms modeled with a nanodot on the phantom surface ranged between 2.7 to 3.2 mm. In allmore »
 Authors:
 Univ Washington, Seattle, WA (United States)
 Publication Date:
 OSTI Identifier:
 22496269
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Medical Physics; Journal Volume: 42; Journal Issue: 6; Other Information: (c) 2015 American Association of Physicists in Medicine; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 61 RADIATION PROTECTION AND DOSIMETRY; BRAGG CURVE; DEPTH DOSE DISTRIBUTIONS; DOSEMETERS; ENERGY DEPENDENCE; IRRADIATION; MONTE CARLO METHOD; PEAKS; PHANTOMS; PROTON BEAMS; QUANTUM DOTS; SIMULATION; WATER
Citation Formats
Young, L, and Yang, F. SUET553: Monte Carlo Calculation of Proton Bragg Peak Displacements in the Presence of Al2O3:C Dosimeters. United States: N. p., 2015.
Web. doi:10.1118/1.4924915.
Young, L, & Yang, F. SUET553: Monte Carlo Calculation of Proton Bragg Peak Displacements in the Presence of Al2O3:C Dosimeters. United States. doi:10.1118/1.4924915.
Young, L, and Yang, F. Mon .
"SUET553: Monte Carlo Calculation of Proton Bragg Peak Displacements in the Presence of Al2O3:C Dosimeters". United States.
doi:10.1118/1.4924915.
@article{osti_22496269,
title = {SUET553: Monte Carlo Calculation of Proton Bragg Peak Displacements in the Presence of Al2O3:C Dosimeters},
author = {Young, L and Yang, F},
abstractNote = {Purpose: The application of optically stimulated luminescence dosimeters (OSLDs) may be extended to clinical investigations verifying irradiated doses in small animal models. In proton beams, the accurate positioning of the Bragg peak is essential for tumor targeting. The purpose of this study was to estimate the displacement of a pristine Bragg peak when an Al2O3:C nanodot (Landauer, Inc.) is placed on the surface of a water phantom and to evaluate corresponding changes in dose. Methods: Clinical proton pencil beam simulations were carried out with using TOPAS, a Monte Carlo platform layered on top of GEANT4. Pointshaped beams with no energy spread were modeled for energies 100MV, 150MV, 200MV, and 250MV. Dose scoring for 100,000 particle histories was conducted within a water phantom (20cm × 20cm irradiated area, 40cm depth) with its surface placed 214.5cm away from the source. The modeled nanodot had a 4mm radius and 0.2mm thickness. Results: A comparative analysis of Monte Carlo depth dose profiles modeled for these proton pencil beams did not demonstrate an energy dependent in the Bragg peak shift. The shifts in Bragg Peak depth for water phantoms modeled with a nanodot on the phantom surface ranged between 2.7 to 3.2 mm. In all cases, the Bragg Peaks were shifted closer to the irradiation source. The peak dose in phantoms with an OSLD remained unchanged with percent dose differences less than 0.55% when compared to phantom doses without the nanodot. Conclusion: Monte Carlo calculations show that the presence of OSLD nanodots in proton beam therapy will not change the position of a pristine Bragg Peak by more than 3 mm. Although the 3.0 mm shift will not have a detrimental effect in patients receiving proton therapy, this effect may not be negligible in dose verification measurements for mouse models at lower proton beam energies.},
doi = {10.1118/1.4924915},
journal = {Medical Physics},
number = 6,
volume = 42,
place = {United States},
year = {Mon Jun 15 00:00:00 EDT 2015},
month = {Mon Jun 15 00:00:00 EDT 2015}
}

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