Anti-scatter Grid Motion Profile for Mammography
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current anti-scattering grids in radiography and breast tomosynthesis suffer from residual image artifacts, moiré effects, and increased acceleration stress, making it difficult to achieve clear images due to limited space and interference patterns.
Innovation Solution
A process and device that displaces the anti-scattering grid or detector relative to each other during radiation emission, with a randomized motion pattern to alter return points and phase, using actuators like piezoelectric motors or stepper motors to minimize grid visibility and moiré effects, while adapting the grid pitch to the detector pitch.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the grid is animated by vibration movement perpendicular to the strip direction, then the image of radio-adsorbing strips is erased, but moiré effects and interference figures are created on the detector
Solution Approach 1:
The grid is made dynamically movable rather than static, allowing it to change position during the imaging process. The grid can be displaced along its strip direction by a controlled amount, transforming it from a static obstacle to a dynamic element that adapts its position to eliminate artifacts.
Solution Approach 2:
The grid displacement is implemented as a periodic movement during the radiation emission period. By moving the grid back and forth through its strips along the strip direction, the system creates a time-varying configuration that prevents both grid line visibility and moiré effect formation.
2Adaptability or versatility
If the grid strips are oriented parallel to the chest wall in breast tomosynthesis, then the focusing line can be maintained in the source plane, but the space for grid displacement perpendicular to strips is limited
Solution Approach 1:
The grid is made dynamically movable rather than static, allowing it to change position during the imaging process. The grid can be displaced along its strip direction by a controlled amount, transforming it from a static obstacle to a dynamic element that adapts its position to eliminate artifacts.
Solution Approach 2:
Instead of moving the grid perpendicular to the strips (which is constrained by the limited space between chest wall and detector), the invention moves the grid along the strip direction. This dimensional change in movement direction resolves the space constraint while maintaining the grid's functional orientation.
3Object-affected harmful factors
If fixed frequency or amplitude grid movement is used, then the grid can be animated to erase strip images, but acceleration stress increases and return point shadows are created
Solution Approach 1:
The grid movement parameters (frequency, amplitude, and phase) are made variable rather than fixed. By dynamically adjusting these parameters during the imaging process, the system optimizes the balance between erasing strip images and minimizing acceleration stress and return point shadows.
Solution Approach 2:
The grid displacement is implemented as a periodic movement during the radiation emission period. By moving the grid back and forth through its strips along the strip direction, the system creates a time-varying configuration that prevents both grid line visibility and moiré effect formation.
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
This approach effectively eliminates grid images, shadows, and moiré patterns, reducing acceleration stress and enhancing image clarity and contrast, allowing for a wider range of materials to be used and improving the quality of radiographic and 3D mammographic images.
Implementation Method 1
the scattered photons are absorbed by the radio-opaque strips and the photons coming directly from the source 1 are transmitted to the detector 3
Implementation Method 2
using actuators like piezoelectric motors or stepper motors
Data Source
AI summary
A process for deploying an anti-scattering grid in a mammograph is provided. The mammograph comprises a radiation source configured to emit radiation for taking mammographic images of a patient, a radiation detector comprising a network of sensors arranged periodically with a first pitch, and an anti-scattering grid arranged between the source and the detector, the anti-scattering grid comprising radiation adsorbing strips arranged parallel to each other and distributed periodically with a second pitch. The process comprises: displacing the anti-scattering grid relative to the detector or displacing the detector relative to the anti-scattering grid during emission of radiation; adapting the second pitch to the first pitch, wherein displacement is perpendicular to the direction of the strips of the anti-scattering grid, the strips being arranged parallel to a side of the anti-scattering grid positioned against the patient, and altering the positions of the return points between successive periods of the displacement motion.