Dynamic Motion Compensation Limits in Radiation Therapy Plans
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current radiation treatment plans face challenges in effectively discriminating between target structures and adjacent tissues, leading to compromised therapy efficacy due to physical and safety limitations in motion compensation during radiation delivery.
Innovation Solution
Configuring radiation-delivery treatment plans with adjustable limit values for motion compensation based on preselected parameters, allowing for dynamic adjustments of radiation-delivery parameters such as collimator position and gantry orientation, to optimize radiation dosage delivery across varying treatment positions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single limit value is used for motion compensation throughout the treatment session, then the treatment apparatus operates within safe and physically feasible boundaries, but the therapeutic efficacy is reduced due to unnecessary restrictions during portions of the treatment where greater compensation is acceptable
Solution Approach 1:
The patent applies dynamics by transitioning from a static, single limit value for motion compensation to a dynamic, time-varying limit value that changes throughout the treatment session. The limit is configured to be more restrictive during portions where patient motion is expected and less restrictive during portions where motion is minimal, allowing the system to adapt its compensation capabilities to the actual treatment conditions at each moment.
Solution Approach 2:
The patent applies preliminary action by pre-configuring different limit values for different time periods or portions of the treatment session before the treatment begins. The treatment plan specifies in advance which limit values apply during different phases of the arc therapy, allowing the system to be prepared with optimized compensation parameters for each segment of the treatment.
2Productivity
If motion compensation adjustments are permitted without limits, then therapeutic efficacy is maximized by tracking tumor motion, but the treatment apparatus may attempt physically impossible or unsafe compensation adjustments
Solution Approach 1:
The patent applies parameter changes by modifying the limit parameter for motion compensation based on the specific conditions of different treatment portions. By changing the limit parameter values according to the treatment phase, the system optimizes the balance between allowing sufficient motion compensation for therapeutic efficacy while maintaining physical feasibility and safety constraints appropriate for each segment of the treatment.
3Reliability
If a restrictive limit is applied to motion compensation, then safety constraints are satisfied and physical limitations are respected, but the ability to compensate for patient motion is insufficient, reducing treatment precision
Solution Approach 1:
The patent resolves this contradiction by making the motion compensation limit dynamic rather than static. During portions of the treatment where patient motion is anticipated, more restrictive limits are applied to ensure safety and physical feasibility. During portions where motion is minimal or the beam geometry is more favorable, less restrictive limits are applied to allow greater compensation precision, thereby optimizing both safety and precision throughout the treatment session.
Data Source
AI summary
A radiation-delivery treatment plan includes a first value for a limit as pertains to motion compensation-based adjustment of a radiation-delivery parameter during a first portion of a radiation treatment session as well as a second value for that same limit during a second, different portion of the treatment session. By one approach, the radiation-delivery treatment plan selects between this first and second value as a function of a preselected parameter. Examples of such parameters include, but are not limited to, radiation-beam orientation parameters (such as a gantry-based parameter) and/or any of a variety of external surrogates.