Fast Monte Carlo Cell-By-Cell Simulation of Radiation-Induced DNA Damage, Chromosome Aberrations, and Cell Death for Low-Dose-Rate Brachytherapy Sources

The development of new tools for the modeling and simulation of radiation damage to DNA and the resulting chromosome aberrations has enabled studies of cell survival characteristics to be performed via computer simulation. TOPAS, a Monte Carlo based physics modeling tool, contains models of the brachytherapy sources commonly used in radiation therapy for the treatment of cancer patients. TOPAS-nBio, an extension of the TOPAS modeling tool, allows the generation of standard DNA damage (SDD) files on a particle-by-particle and cell-by-cell basis. MEDRAS, a mechanistic DNA repair and survival model, is capable of calculating various types of chromosome aberrations and determining whether a cell remains viable using the corresponding SDD file generated by TOPAS-nBio. Rather than utilizing the computationally intensive TOPAS-nBio to produce the SDD file for each exposure scenario and for each cell, code was developed to rapidly generate SDD files based on pre-computed single-electron-track SDD libraries for each electron energy interacting with the cell nucleus. By combining the TOPAS brachytherapy modeling, rapid SDD generating code, and MEDRAS analysis, rapid calculations of DNA double strand breaks, chromosome aberrations, and cell survival curves for brachytherapy sources is demonstrated, analyzed and compared with various in vitro studies found in the literature.

Level thesis:degree_level

Doctoral

Department dc:contributor.department

Mechanical Engineering

Grantor dc:publisher

Georgia Institute of Technology

Year dc:date.issued

2025

Author dc:creator

• Dick, Joseph S.

Advisor dc:contributor.advisor

• Wang, C.-K. Chris

Committee members dc:contributor.committeemember

• Biegalski, Steven
• Dewji, Shaheen
• Erickson, Anna
• Elder, Eric

• LDR
• brachytherapy
• in-silico
• chromosome aberrations
• radiation therapy
• low dose rate
• MEDRAS
• TOPAS-nBio
• DNA

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/1853/81474

OAI identifier oai:identifier

oai:repository.gatech.edu:1853/81474