A graphical user interface for Monte Carlo dose calculations for brachytherapy with egs_brachy.

Background: Recent advancements in brachytherapy necessitate precise dose calculations, transitioning from the traditional TG43 planning methods to the more sophisticated TG186 recommendations. However, the availability of accessible and efficient Monte Carlo (MC) codes capable of interfacing with clinical data for these advanced calculations remains limited.

Purpose: This study presents and validates eb_gui, a graphical user interface designed to seamlessly integrate DICOM clinical data with egs_brachy, a fast MC dose calculation algorithm tailored for brachytherapy applications.

Methods: The egs_brachy graphical user interface (eb_gui) was developed using C++ with the Qt5 framework. Five benchmarking scenarios were employed to validate the use of eb_gui. Simulations were compared against three non-clinical test cases developed by the joint Working Group on Model-Based Dose Calculations (WG-MBDC), assessing local and global dose difference ratios with reference MC data. An interstitial HDR breast case and a low dose rate (LDR) prostate case were also analyzed, evaluating dose difference histograms, dose ratio maps, dose-volume histograms, and extracted dose metrics.

Results: For the three WG-MBDCA test cases, over 95% of evaluated voxels showed local dose differences of less than ± 0.40%, with all voxels demonstrating global dose differences within ± 0.02%. In the interstitial HDR breast case, over 95% of voxels exhibited global difference ratios within [-0.31%, +0.39%] relative to the reference dataset, while local difference ratios varied due to simulation conditions. Results of the LDR prostate test case simulations underscored the eb_gui's comprehensive capabilities and accuracy.

Conclusion: eb_gui successfully bridges clinical data with egs_brachy MC simulations, facilitating advanced, patient-specific dose evaluations in accordance with TG186 recommendations. By releasing eb_gui as open-source software on GitHub, this study promotes widespread adoption within the clinical community, supporting the move toward more accurate and personalized brachytherapy treatments. This tool represents a significant advancement, enabling clinicians to conduct high-quality MC dose calculations efficiently.