2024
12:00 PM - 01:00 PM
Tuesday Tue
Location
Medical Physics Seminar - Xun Jia
Modeling Radiobiology Outcomes Using Microscopic Monte Caro simulations
Time:
12:00pm – 1:00pm Seminar & Discussion
Location:
Zoom Webinar
Webinar Registration:
https://stanford.zoom.us/webinar/register/WN_mLs37y4bQDqrz2zGobLn4g
Check your email for the Zoom webinar link after you have registered
Speaker
Dr. Xun Jia, Ph.D., Chief of Medical Physics Division at The Johns Hopkins University, School of Medicine
Dr. Xun Jia is Professor and Chief of the Medical Physics Division within the Department of Radiation Oncology and Molecular Radiation Sciences at the Johns Hopkins University School of Medicine. He earned his Ph.D. in physics from the University of California Los Angeles in 2009 and received postdoctoral training in medical physics at the Department of Radiation Oncology and Applied Sciences, University of California San Diego, from 2009 to 2011. Before joining Johns Hopkins University in 2022, Dr. Jia served as Professor and Associate Vice Chair of Medical Physics Research in the Department of Radiation Oncology at the University of Texas Southwestern Medical Center. Additionally, he was the founding Director of the CAMPEP- accredited Medical Physics graduate program at the institution. Throughout his career, Dr. Jia has been actively involved in impactful research, contributing to areas such as medical image reconstruction, GPU-based Monte Carlo radiation transport simulation, deep learning applications for image processing and radiotherapy treatment planning, and the advancement of technologies for preclinical small animal radiation research. His has published over 170 peer-reviewed manuscripts, and his research endeavors have received support from federal, state, industrial, and charitable funding agencies. Dr. Jia currently serves as Executive Editorial board member for the Physics in Medicine and Biology journal, as well as the position of Associate Editor for the Medical Physics journal and several other journals. Recognizing his significant contributions to the field, he was honored with the 2017 John Laughlin Young Scientist Award and is a Fellow of the American Association of Physicists in Medicine.
Abstract
Radiation dose has long been the primary metric used in radiotherapy to model treatment outcomes. However, growing evidence indicates that dose alone is insufficient to capture the full spectrum of biological responses to radiation. To address this, additional factors are often introduced to account for variations under different irradiation conditions specified by terms such as dose rate and linear energy transfer (LET). Given that DNA is the primary target of radiation, directly modeling radiation-induced DNA damage, as well as how it is modulated by irradiation conditions, are expected to provide a more accurate predictor of biological effects. In this presentation, we explore the application of GPU-accelerated microscopic Monte Carlo (MC) simulations to model radiation-induced DNA damage at the molecular level and analyze its subsequent biological effects. By simulating the physical and chemical stages of water radiolysis, we track the formation of reactive species and their interaction with DNA, leading to damage. We present an overview of this DNA damage generation process and demonstrate how comprehensive microscopic MC modeling yields deeper insights into biological responses to radiation. Several case studies will illustrate the impact of different irradiation conditions on DNA damage and biological outcomes, such as LET in proton therapy and dose rate in FLASH therapy.