Tomosynthesis Radiography Apparatus Slice Thickness Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In tomosynthesis radiography, slice images with consistent slice thickness are difficult to generate due to varying slice angles and positions, leading to inconsistent image resolution in the depth direction.
Innovation Solution
A radiography apparatus that moves the radiation source based on a calculated movement range defined by a desired slice angle and base point, selecting radiographic images based on distance from the detection surface and slice plane to ensure consistent slice thickness across different positions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If all radiographic images obtained by radiography are used to generate a slice image of each slice plane, then the slice image can be generated with sufficient data, but the slice thickness becomes inconsistent depending on the position in the depth direction
Solution Approach 1:
The patent applies local quality by selecting radiographic images based on the specific slice plane position in the depth direction. Different slice planes use different subsets of radiographic images, with the selection determined by the distance from the detection surface and the desired slice angle. This ensures that each slice image is reconstructed using only the appropriate images, maintaining consistent slice thickness across different depths.
Solution Approach 2:
The patent changes the parameter of image selection based on the slice plane position. By calculating the distance from the detection surface to each slice plane and using the desired slice angle, the system dynamically determines which radiographic images to use for reconstruction. This parameter-based selection approach resolves the inconsistency in slice thickness that would otherwise occur when using all images for all slice planes.
2Measurement precision
If the slice angle is increased to improve divisibility in the thickness direction, then the slice thickness becomes thinner and resolution improves, but the movement range of the X-ray tube must be increased
Solution Approach 1:
The patent applies partial action by selecting only the necessary radiographic images for reconstructing each slice plane, rather than using all available images. By calculating the appropriate range of images based on the desired slice angle and slice plane position, the system achieves the desired slice thickness without requiring the X-ray tube to traverse the full possible range, thus reducing the actual movement range needed.
3Measurement precision
If radiographic images are selected based on distance from detection surface and slice plane position, then consistent slice thickness is achieved, but the reconstruction process becomes more complex
Solution Approach 1:
The patent applies preliminary action by pre-calculating the movement range of the X-ray tube and pre-determining which radiographic images should be used for each slice plane position. This preliminary selection based on distance from the detection surface and desired slice angle simplifies the actual reconstruction process, as the appropriate images are already identified before reconstruction begins, reducing the complexity of the reconstruction algorithm itself.
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
Enables the generation of slice images with substantially the same thickness regardless of the slice plane position, improving image resolution and consistency by selecting appropriate radiographic images for reconstruction.
Implementation Method 1
a radiation source that outputs radiation to a subject; a detection means that detects the radiation that has passed through the subject
Data Source
AI summary
A radiation source is moved, relative to a detection means, in a movement range that is calculated based on a desired slice angle with respect to a predetermined base point on a base plane that defines a range of obtaining a slice image of a subject. The radiation source is moved to a plurality of positions, and a plurality of radiographic images of the subject corresponding to the plurality of positions are obtained by irradiating the subject with radiation from the plurality of positions. Further, a slice image of the subject is reconstructed from the plurality of radiographic images. When the slice image is reconstructed, radiographic images to be used to reconstruct the slice image are selected based on a distance from the detection surface of the detection means to a slice plane on which the slice image is to be generated, and the desired slice angle.