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arXiv · 2110.10733

Meta-optimization for Fully Automated Radiation Therapy Treatment Planning

Charles Huang·Yusuke Nomura·Yong Yang·Lei Xing
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Abstract

Objective: Radiation therapy treatment planning is a time-consuming process involving iterative adjustments of hyperparameters. To automate the treatment planning process, we propose a meta-optimization framework, called MetaPlanner (MP). Methods: Our MP algorithm automates planning by performing optimization of treatment planning hyperparameters. The algorithm uses a derivative-free method (i.e. parallel Nelder-Mead simplex search) to search for weight configurations that minimize a meta-scoring function. Meta-scoring is performed by constructing a tier list of the relevant considerations (e.g. dose homogeneity, conformity, spillage, and OAR sparing) to mimic the clinical decision-making process. Additionally, we have made our source code publicly available via github. Results: The proposed MP method is evaluated on two datasets (21 prostate cases and 6 head and neck cases) collected as part of clinical workflow. MP is applied to both IMRT and VMAT planning and compared to a baseline of manual VMAT plans. MP in both IMRT and VMAT scenarios has comparable or better performance than manual VMAT planning for all evaluated metrics. Conclusion: Our proposed MP provides a general framework for fully automated treatment planning that produces high quality treatment plans. Significance: Our MP method promises to substantially reduce the workload of treatment planners while maintaining or improving plan quality.

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Charles Huang, Yusuke Nomura, Yong Yang, Lei Xing. 2021-10-20. Meta-optimization for Fully Automated Radiation Therapy Treatment Planning. https://doi.org/10.1088/1361-6560%2Fac5672

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