Calibration Phantom for Radiotherapy Alignment Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a lack of satisfactory quality maintenance procedures for image-based radiotherapy apparatuses, which are the latest medical devices, leading to potential radiation damage to normal tissues during tumor treatment due to the inability to accurately observe and adjust the tumor's status in real-time.
Innovation Solution
A calibration phantom is installed on the image-based radiotherapy apparatus, comprising a cylindrical acryl member with density bars and bolts of different materials, a disk-shaped plug, and a glass bead, designed to be imaged by both the CT and radiation treatment machines, allowing for precise adjustment and quality assurance of the imaging and radiation treatment machines.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a calibration phantom is designed to be imaged by both CT and radiation treatment machines, then the alignment precision between imaging and radiation treatment machines is improved, but the device complexity increases
Solution Approach 1:
The calibration phantom is designed with multi-functional elements that can be imaged by both CT machines and radiation treatment machines. The phantom includes cylindrical targets with specific geometric features and density variations that are visible across different imaging modalities, allowing a single device to serve multiple calibration purposes for both imaging and radiation treatment systems.
Solution Approach 2:
The phantom incorporates regions with different material densities and compositions at specific locations. These local variations in density and material properties create distinct imaging characteristics in different modalities, enabling precise localization and alignment verification without requiring the entire phantom to be complex.
2Reliability
If quality assurance procedures are established for image-based radiotherapy apparatus, then the reliability of radiation treatment is improved, but the time required for calibration and quality checks increases
Solution Approach 1:
The calibration phantom enables preliminary alignment and quality verification to be performed before actual patient treatment. By establishing the correct geometric relationship between imaging and radiation treatment systems in advance using the phantom, the system ensures reliable treatment delivery without requiring extensive time-consuming checks during each patient procedure.
Solution Approach 2:
The phantom provides self-verifying features where the alignment and calibration status can be assessed directly from the acquired images without requiring complex external measurement devices or procedures. The geometric features and density variations in the phantom allow the system to self-validate its calibration state.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The calibration phantom enhances the precision of radiation treatment by ensuring accurate alignment of the imaging and radiation treatment machines, thereby increasing treatment success rates and preventing radiation damage to normal tissues.
Implementation Method 1
The CT apparatus is a device taking images based on the differences of the X-ray attenuation coefficient according to changes of electron density
Data Source
AI summary
A calibration phantom for quality assurance of an image-based radiotherapy apparatus The calibration phantom includes a body comprising a cylindrical acryl member having a predetermined diameter, the body having a center hole at a center axis thereof and a plurality of through-holes in outer circumferential portions thereof at a predetermined interval from the center hole; round stick-type density bars inserted into corresponding through-holes of the body and made of materials each with different densities; an acrylic cover detachably coupled with both ends of the body and having the same diameter as the body; and a plurality of bolts closely fastening the body with the cover by extending through the cover and the body and coupling with the nuts and each made of different materials. The cross-sectional shapes of the density bars and bolts appear on the image scanned by the CT apparatus and the radiotherapy apparatus.