Program Information
Proton Treatment Planning On a Moby Mouse Phantom Using Varian Eclipse and TOPAS
E Abel1*, A Katsis2 , J Perl3 , (1) Varian Medical Systems, Palo Alto, California, (2) ,,,(3) Stanford Linear Accelerator Center, Menlo Park, CA
Presentations
SU-E-FS1-8 (Sunday, July 30, 2017) 1:00 PM - 1:55 PM Room: Four Seasons 1
Purpose: In preclinical studies, it is often desirable to control the dose uniformity to an organ of interest while simultaneously minimizing dose to critical organs, which may undesirably affect the experimental outcome. This study combines the use of a Moby digital mouse phantom (Carl E. Ravine Advanced Imaging Laboratories), Varian Eclipse™ 13.7 treatment planning software (TPS) and the TOPAS Monte Carlo Tool for Particle Simulation to optimize a mouse lung proton irradiation.
Methods: Digital mouse volumes by CT number for full inhale and exhale phases were generated using the Moby digital phantom generator. The CT volumes were then imported into Eclipse™ 13.7, the organs segmented, and the dose calculated using ProBeam™ configured beam data in the Proton Convolution Superposition (PCS) algorithm. Dose to the Lung, Spleen, Bowel and Brain were evaluated, and manually optimized. The plans were further verified using a pre-release version of TOPAS 3.1 that adds a built-in reader for the Carl Levin phantoms (XCAT, Moby, Roby). The reader was set to apply the ICRP 1975 defined material compositions to the associated organs.
Results: We were able to generate a plan robust against mouse positioning errors (up to 3 mm), as well as lung motion, all while meeting the following dose criteria: 20 Gy lung dose with 80% coverage, <5 Gy spleen dose, <7 Gy bowel dose, < 15 Gy brain dose. The plan was successfully verified in TOPAS.
Conclusion: We have demonstrated a feasible approach to using an off-the-shelf Varian Eclipse TPS and TOPAS to plan and evaluate proton dose to a digital mouse phantom, thereby demonstrating the utility of these tools in preclinical dose planning.
Funding Support, Disclosures, and Conflict of Interest: Eric Abel and Alexander Katsis are employees of Varian Medical Systems.
Contact Email: