Analysis of Bragg Curve Parameters and Lateral Straggle for Proton and Carbon Beams

TL;DR

This study compares the Bragg curve parameters and lateral straggle of proton and carbon beams in tissue, providing insights into their suitability for tumor treatment through simulations and calculations.

Contribution

It offers a detailed comparison of proton and carbon ion beam characteristics, including dose distribution and lateral straggle, using TRIM and Monte Carlo simulations.

Findings

Protons have 63% more FWHM and 53% more Penumbra than carbon ions.

Carbon ions exhibit 28-45 times greater Bragg peak amplitude than protons.

Protons scatter approximately 70% more in lateral straggle, around 1.32 mm.

Abstract

Heavy ions have varying effects on the target. The most important factor in comparing this effect is Linear Energy Transfer (LET). Protons and carbons are heavy ions with high LET. Since these ions lose energy through collisions as they move through the tissue, their range is not long. This loss of energy increases along the way, and the maximum energy loss is reached at the end of the range. This whole process is represented by the Bragg curve. The input dose of the Bragg curve, full width at half maximum (FWHM) value, Bragg peak amplitude and position, and Penumbra thickness are important factors in determining which particle is advantageous in tumor treatment. While heavy ions move through the tissue, small deviations occur in their direction of travel due to Coulomb collisions. These small deviations cause lateral straggle in the dose profile. Lateral straggle is important in determining the type and energy of the particle used in tumor treatments close to critical organs. In our study, when the water phantom of protons and carbon beams with different energies is taken into consideration, the input dose, FWHM value, peak amplitude and position, penumbra thickness and lateral straggle are calculated using the TRIM code and the results are compared with Monte Carlo (MC) simulation. It was found that the proton has an average of 63% more FWHM and 53% more Penumbra than the carbon ion. The carbon ion has an average of 28-45 times greater Bragg peak amplitude at the same Bragg peak location than the proton. It was observed that the proton scattered approximately 70% more in lateral straggle. The difference was found to be around 1.32 mm. In line with all these results, the most commonly used proton and carbon heavy ions in hadron therapy applications were compared.