System and method for inverse treatment planning for radiation therapy

A system for determining a treatment plan for a radiation therapy system, comprising:

• the radiation therapy system configured with adjustable beam shape settings to adjust a spatial dose delivered to a subject;
• a computer system configured to:
• i) determine a three-dimensional region of interest (ROI) in the subject containing a critical structure;
• ii) divide the ROI into a grid of dose voxels;
• iii) model a radiation dose fluence map for the grid of dose voxels as delivered by the radiation therapy system with a plurality of beamlets to create a modeled radiation dose fluence map, each having a beamlet fluence;
• iv) determine a voxel-based fluence map optimization (FMO) model for the modeled radiation dose fluence map;
• v) determine a conic optimization formulation for the FMO model to create a determined optimization solution;
• vi) generate an optimized fluence map by updating the modeled radiation dose fluence map with the determined conic optimization solution;
• vii) determine the beam shape settings for the optimized fluence map;
• and
• a display configured to display the optimized fluence map.

A method of determining a treatment plan for a radiation therapy system, the radiation therapy system comprising a radiation therapy unit, wherein a spatial dose delivered can be changed by adjusting beam shape settings, the method including steps comprising:

• 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;
• modeling an ionizing radiation dose as delivered by a plurality of beamlets each having a beamlet fluence;
• providing a quadratic, power and exponential cone voxel-based model for optimizing a fluence map, said fluence map defining said fluences for each of said plurality of beamlets;
• and
• solving said model based on defined treatment plan clinical objectives and constraints for said at least one target and said at least one critical structure using an interior point algorithm to obtain a globally optimal fluence map.