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. 2021 May;48(5):2580-2591.
doi: 10.1002/mp.14726. Epub 2021 Mar 27.

Monte Carlo computation of 3D distributions of stopping power ratios in light ion beam therapy using GATE-RTion

Marta Bolsa-Ferruz  1 , Hugo Palmans  1   2 , David Boersma  1   3 , Markus Stock  1 , Loïc Grevillot  1
Affiliations

Monte Carlo computation of 3D distributions of stopping power ratios in light ion beam therapy using GATE-RTion

Marta Bolsa-Ferruz et al. Med Phys. 2021 May.

Abstract

Purpose: This paper presents a novel method for the calculation of three-dimensional (3D) Bragg-Gray water-to-detector stopping power ratio (sw,det ) distributions for proton and carbon ion beams.

Methods: Contrary to previously published fluence-based calculations of the stopping power ratio, the sw,det calculation method used in this work is based on the specific way GATE/Geant4 scores the energy deposition. It only requires the use of the so-called DoseActor, as available in GATE, for the calculation of the sw,det at any point of a 3D dose distribution. The simulations are performed using GATE-RTion v1.0, a dedicated GATE release that was validated for the clinical use in light ion beam therapy.

Results: The Bragg-Gray water-to-air stopping power ratio (sw,air ) was calculated for monoenergetic proton and carbon ion beams with the default stopping power data in GATE-RTion v1.0 and the new ICRU90 recommendation. The sw,air differences between the use of the default and the ICRU90 configuration were 0.6% and 5.4% at the physical range (R80 - 80% dose level in the distal dose fall-off) for a 70 MeV proton beam and a 120 MeV/u carbon ion beam, respectively. For protons, the sw,det results for lithium fluoride, silicon, gadolinium oxysulfide, and the active layer material of EBT2 (radiochromic film) were compared with the literature and a reasonable agreement was found. For a real patient treatment plan, the 3D distributions of sw,det in proton beams were calculated.

Conclusions: Our method was validated by comparison with available literature data. Its equivalence with Bragg-Gray cavity theory was demonstrated mathematically. The capability of GATE-RTion v1.0 for the sw,det calculation at any point of a 3D dose distribution for simple and complex proton and carbon ion plans was presented.

Keywords: GATE; GATE-RTion; Geant4; Monte Carlo; carbon ion beam therapy; light ion beam dosimetry; protontherapy; stopping power ratio.

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References

REFERENCES

    1. GiordanengoS, ManganaroL, VignatiAReview of technologies and procedures of clinical dosimetry for scanned ion beam radiotherapy. Phys Medica. 2017;43:79-99.
    1. PalmansHMonte Carlo calculations for proton and ion beam dosimetry. In: Monte Carlo Techniques in Radiation Therapy. Boca Raton: CRC Press; 2016;201-216.
    1. AndreoPMonte Carlo simulations in radiotherapy dosimetry. Radiat Oncol. 2018;13:1-15.
    1. MedinJ, AndreoPMonte Carlo calculated stopping-power ratios, water/air, for clinical proton dosimetry (50-250 MeV). Phys Med Biol. 1997;42:89-105.
    1. LaitanoRF, RosettiMProton stopping powers averaged over beam energy spectra. Phys Med Biol. 2000;45:3025-3043.

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