A linear energy transfer distributions computation method for inhomogeneous medium by using the water equivalent...

Area of Science:

• Medical Physics
• Radiation Oncology
• Biophysics

Background:

• Dose-averaged linear energy transfer (LETd) is crucial for proton therapy planning.
• Monte Carlo (MC) simulations provide accurate LETd but are computationally intensive.
• Efficient methods are needed to derive LETd distributions for clinical applications.

Purpose of the Study:

• To develop a rapid method for calculating 3D LETd distributions in human tissues.
• To validate the method against benchmark MC simulations for clinical proton therapy cases.

Main Methods:

• Utilized MC simulations of proton beam spots in water as a benchmark dataset.
• Integrated water equivalent ratios of human tissues to adapt water-based data.
• Applied the method to single and multiple proton beam spots in phantoms and clinical cases (pelvic, lung).

Main Results:

• Successfully computed 3D LETd distributions for various clinical scenarios.
• Demonstrated rapid calculation of LETd distributions compared to traditional MC methods.
• Achieved acceptable agreement between the proposed method and MC simulations.

Conclusions:

• The developed method offers a fast and accurate approach for determining 3D LETd distributions in proton therapy.
• This technique can significantly reduce computation time for clinical dose planning.
• The findings support the clinical implementation of this accelerated LETd calculation method.