Grant: Discovery Grants Program - Individual

My research field is radiotherapy physics, a field devoted to the use of physics concepts to treat cancer and other diseases with radiation. My research program focuses on two strongly linked domains: radiation measurements, and radiation dose calculations in patients. The long-term vision of my research program is to seek greater understanding of the physics involved in these two domains, then translate this into novel and/or refined physics solutions that facilitate more accurate, efficient and robust radiation measurements and dose calculations. With that vision, the objectives that I am currently exploring are described below.The energy spectrum of the radiation generated by the treatment machine is important for dose calculations and for understanding radiation detectors. I have developed an accurate and practical device for these very challenging spectral measurements. My research group will use the device to explore long standing physics questions regarding the spectral differences among nominally identical (or matched) treatment machines. From this knowledge, we will improve dosimetric machine matching and develop dose calculation models that are robust against machine variations. The group will explore similar questions for other specialized treatment machines with unique characteristics. For radiation detector arrays, we will develop improved methods to make their characterization more accurate and robust.Most radiotherapy patients receive three types of scans: one to diagnose the disease, a special one for treatment planning and dose calculation, and one for positioning before treatment. This is inefficient for patients with urgent need for treatment. My research group is exploring an ambitious new paradigm to use diagnostic and/or positioning scans for treatment planning and dose calculation, eliminating the need for the middle scan. Numerous physics challenges exist in this paradigm, including scanner calibration, undesirable physics effects in scans, patient anatomy changes, disease visibility, and dose calculation accuracy. I am using my expertise to lead the development of physics solutions to these challenges using state-of-the-art radiation facilities, simulation methods, correction algorithms, and image deformation software.Radiation dose received by healthy organs such as the bowel is important for side effects and treatment outcomes. Accurate estimate of bowel dose is very challenging due to bowel mobility and ambiguity in scans, with limited success to date. My group is developing a physics platform that includes characterization of bowel daily changes, as well as a novel approach to automate bowel identification using its boundary organs. These are our building blocks towards accurate bowel dose estimates.The improved accuracy, efficiency and robustness in the areas above will lead to higher-quality, cost-effective radiotherapy.