Conic Optimization for Radiation Therapy Fluence Maps

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current fluence map optimization methods in radiation therapy do not guarantee globally optimal solutions and are often restricted to specific problem forms, lacking efficiency and accuracy in achieving the desired trade-off between treatment plan evaluation criteria.

Innovation Solution

The use of conic optimization formulations to model fluence map optimization problems, enabling the application of advanced numerical solvers and ensuring globally optimal solutions by formulating dose-based and biologically-based criteria as convex optimization problems.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional optimization methods (sequential quadratic programming, conjugate gradient, L-BFGS, barrier methods) are used to solve fluence map optimization problems, then treatment planning can be performed, but the solutions are not guaranteed to be globally optimal and the methods are restricted to specific problem forms

Engineering Contradiction:
Improveguarantee of globally optimal solutionVSAvoidapplicability to different problem forms
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent transforms the optimization problem by changing the mathematical formulation from conventional methods to conic optimization. This parameter change in the problem representation enables guaranteed global optimality while maintaining versatility across different problem forms through standardized conic programming techniques.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The conic optimization framework provides a universal approach that can handle various fluence map optimization problems with different evaluation criteria (dose-based, biologically-based) within a single unified mathematical structure, eliminating the need for problem-specific specialized methods.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Manufacturing precision

If advanced numerical solvers are used to solve large-scale optimization problems, then fluence map optimization can be achieved, but the computational time and complexity increase

Engineering Contradiction:
Improveoptimization solution qualityVSAvoidcomputational time for optimization
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

By reformulating the optimization problem as a conic programming problem, the patent enables the use of efficient conic solvers that can handle large-scale problems faster. The conic formulation transforms complex non-convex problems into convex problems that can be solved more efficiently with modern numerical methods.

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If conventional optimization methods are used, then treatment planning can be performed, but the methods do not guarantee optimal trade-offs between various treatment plan evaluation criteria

Engineering Contradiction:
Improvetreatment plan evaluationVSAvoidoptimality of trade-off between criteria
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The conic optimization framework provides a unified approach that can handle multiple evaluation criteria (dose-based, biologically-based) simultaneously within a single optimization problem, ensuring optimal trade-offs are achieved through the convex optimization properties of conic programming.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentUS20240198133A1System and method for inverse treatment planning for radiation therapy
Publication Date: 2024.06.20 THE GENERAL HOSPITAL CORP
  • US20240198133A1 patent drawing
  • US20240198133A1 patent drawing
  • US20240198133A1 patent drawing

AI summary

Systems and methods are provided for determining a treatment plan for a radiation therapy system. The method includes dividing a three-dimensional volume of a patient into a grid of dose voxels, wherein at least a portion of said dose voxels are designated to belong to at least one target or to at least one critical structure. The method also includes modeling an ionizing radiation dose as delivered by a plurality of beamlets each having a beamlet fluence, to create a modeled radiation dose fluence map. The method also includes determining a voxel-based fluence map optimization (FMO) model for the modeled radiation dose a fluence map. The method also includes determining a conic optimization formulation for the FMO model to create a determined conic optimization solution and generating an optimized fluence map by updating the modeled radiation dose fluence map with the determined conic optimal fluence map.