Tomosynthesis Depth Resolution via Geometric Reconstruction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The calculation of thicker slices in tomosynthesis requires adapting depth information to the recording geometry, which is not aligned parallel to a Cartesian coordinate system, leading to suboptimal depth resolution and image quality.
Innovation Solution
A method involving the recording and reconstruction of projection datasets along a linear trajectory with an X-ray source and detector moving in parallel, where depth information is determined along an X-ray beam bundle spanned by the motion and X-ray beam fan perpendicular to the linear trajectory, allowing for different depth levels to be scanned differently, enabling the generation of slice images with varying thickness based on the tomosynthesis dataset.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If depth information is determined using conventional Cartesian coordinate system alignment, then the reconstruction process is simpler, but the depth resolution and image quality deteriorate
Solution Approach 1:
The patent changes the coordinate system parameters from conventional Cartesian alignment to a coordinate system adapted to the specific recording geometry. This involves transforming how depth information is calculated and represented, allowing the system to achieve superior depth resolution by matching the computational framework to the physical acquisition geometry rather than using a fixed Cartesian approach.
Solution Approach 2:
The patent introduces an additional dimensional consideration by accounting for the angular relationships and geometric transformations between the X-ray source trajectory and the detection surface. This dimensional adaptation allows depth information to be reconstructed more accurately by considering the three-dimensional geometry of the acquisition process rather than projecting onto simple Cartesian planes.
2Measurement precision
If thicker slices are calculated using conventional methods, then the coverage area increases, but the image quality and localization precision deteriorate due to blurring
Solution Approach 1:
The patent applies local quality by determining depth information differently for different depth levels within the object. Rather than using a uniform reconstruction approach, the system adapts the depth calculation to account for the specific geometry at each depth level, allowing thicker slices to be generated while maintaining localization precision through localized geometric correction.
Solution Approach 2:
The patent changes the reconstruction parameters based on the recording geometry, allowing the system to calculate thicker slices without the conventional blurring effect. By transforming how depth information is computed across different slices and adapting to the angular relationships in the acquisition geometry, the system maintains image quality even when increasing slice thickness for broader coverage.
3Measurement precision
If different depth levels are scanned uniformly, then the acquisition process is simpler, but the depth resolution and image quality for specific anatomical features deteriorate
Solution Approach 1:
The patent implements local quality by scanning and reconstructing different depth levels with different parameters optimized for their specific geometric relationships. Each depth level is processed according to its unique angular relationships with the X-ray source trajectory, improving depth resolution for specific anatomical features while the system manages the increased complexity through automated geometric calculations.
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 improves the depth resolution and image quality by aligning the scanning with the specific recording geometry, allowing for more accurate calculation of slice images, particularly thicker slices, and reduces blurring, enabling precise localization of anatomical features and generation of continuous slice image sequences with consistent quality.
Implementation Method 1
an X-ray source and an X-ray detector move in parallel opposite to one another along the linear trajectory
Data Source
AI summary
A method includes recording a plurality of projection recordings along a linear trajectory. An X-ray source and an X-ray detector move in parallel opposite to one another along the linear trajectory and the examination object is arranged between the X-ray source and the X-ray detector. The method includes reconstructing a tomosynthesis dataset, respective depth information of the examination object is respective determined along an X-ray beam bundle spanned by the motion along the linear trajectory and an X-ray beam fan of the X-ray source perpendicular to the linear trajectory so that different respective depth levels in the object parallel to a detection surface of the X-ray detector are respectively scanned differently. Finally, the method includes determining a first slice image with a first slice thickness in a depth level, among the respective depth levels, substantially parallel to the detection surface of the X-ray detector based on the tomosynthesis dataset.