Radiation Beam Positioning via External Target Correlation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In radiation therapy, particularly for moving targets like tumors in the lung or liver, existing methods fail to minimize radiation exposure to surrounding tissue, as they often require significant radiation to accurately position the beam.
Innovation Solution
A data processing method that correlates the radiation beam's position with the target's position using external and target position data, employing a correlation model to predict target positions during repetitive motion cycles, and verifies these positions using additional imaging devices to reduce unnecessary radiation exposure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If imaging devices are used to continuously track target position, then positioning precision is improved, but radiation exposure to surrounding tissue increases
Solution Approach 1:
The system performs preliminary imaging during a setup phase to establish a correlation model between external marker positions and internal target positions. This preliminary action allows the target position to be predicted during treatment without continuous imaging, thereby reducing radiation exposure while maintaining positioning precision.
Solution Approach 2:
External markers are introduced as intermediary objects that can be tracked without radiation. The correlation model acts as a mediator that translates external marker positions into internal target position predictions, eliminating the need for continuous radiation-based imaging during treatment.
2Measurement precision
If radiation-based imaging is used to verify target position, then measurement accuracy is improved, but the harmful radiation dose to the patient increases
Solution Approach 1:
Instead of continuous verification imaging, the system performs partial verification only when needed - specifically when the correlation model needs validation or when unexpected movements are detected. This partial action maintains measurement accuracy while minimizing unnecessary radiation exposure.
Solution Approach 2:
The system uses feedback from external marker tracking and correlation model predictions to determine when verification imaging is necessary. The feedback mechanism allows the system to maintain accuracy by performing verification only when prediction uncertainty arises, rather than continuous verification.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to a data processing method for correlating the position of a radiation beam with the position of a target to be irradiated and contained in a structure underlying a repetitive motion comprising a plurality of successive motion cycles, the method comprising the following steps which are constituted to be executed by a computer: a) acquiring, at a processor of the computer, first external position data, second external position data and third external position data from a tracking system, describing the position of at least one external feature of said structure, for one or more sections of at least one first motion cycle occurring during a first period of time, for one or more sections of at least one second motion cycle occurring during a second period of time, and for one or more sections of at least one third motion cycle occurring during said second period of time, respectively; b) acquiring, at the processor of the computer, first target position data and second target position data from a first imaging device, describing the position of said target for at least one of said sections of said at least one first motion cycle, and for said sections of said at least one second motion cycle, respectively; c) determining, by the processor of the computer and based on said first external position data and said first target position data, correlation model data describing a positional correlation of said external position and said target position; d) determining, by the processor of the computer and based on said correlation model data and said second external position data, second predicted target position data describing a predicted position of said target for one or more sections of said at least one second motion cycle; e) determining, by the processor of the computer and based on said second target position data and said second predicted target position data, primary verification data describing whether the position of said target for said sections of said at least one second motion cycles is different from said predicted position; f) acquiring, at the processor of the computer and in case said primary verification data indicates that the position of said target is not different from the predicted position of said target, auxiliary second target position data and auxiliary third target position data from a second imaging device, describing the position of said target for one or more sections of said at least one second motion cycle, and of said at least one third motion cycle, respectively; g) determining, by the processor of the computer and based on said first and/or said second external position data, said auxiliary second target position data and said third external position data, third predicted target position data describing a predicted position of said target for said sections of said at least one third motion cycle; h) determining, by the processor of the computer and based on said auxiliary third target position data and said third predicted target position data, secondary verification data describing whether the position of said target for said sections of said at least one third motion cycle is different from said predicted position.