X-Ray CT Reconstruction With Visibility Windows for Motion Artefact Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Motion artefacts in CT image reconstruction due to organ movement during scanning, particularly affecting organs like the heart and lungs, are not adequately addressed by existing CT scanners, leading to blurred and deteriorated tomographic slices.
Innovation Solution
A processing arrangement that selects a sub-range of projection data for each slice based on identified temporal or angular sub-windows of visibility of anatomical features or events, such as heart phases, to reduce the time period covered by the reconstructed image, thereby minimizing motion artefacts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the entire projection data range is used for each slice, then the complete anatomical structure is captured, but motion artefacts increase due to longer acquisition time
Solution Approach 1:
The projection data is segmented into multiple sub-ranges based on temporal or angular criteria. Each sub-range corresponds to a specific phase of the anatomical cycle (e.g., cardiac phase), allowing the data to be divided into manageable portions that minimize motion artefacts while maintaining diagnostic quality.
Solution Approach 2:
Instead of using the complete projection data range, the invention selectively uses only the necessary partial sub-range of data corresponding to the anatomical phase of interest. This partial action approach reduces the acquisition time window, thereby minimizing motion artefacts while still capturing the required anatomical information.
2Object-affected harmful factors
If the acquisition time period is reduced to minimize motion, then motion artefacts decrease, but the temporal resolution and coverage of the reconstructed image deteriorate
Solution Approach 1:
The invention dynamically adjusts the selection of sub-ranges based on the specific anatomical cycle phase and the required temporal resolution. The processing arrangement adapts the data selection strategy to the clinical scenario, optimizing the balance between reducing motion artefacts and maintaining adequate temporal coverage for the specific anatomical structure being imaged.
Solution Approach 2:
The invention changes the temporal and angular parameters of data selection based on the anatomical cycle phase. By adjusting these parameters dynamically, the system optimizes the trade-off between acquisition time window (to minimize motion) and temporal resolution (to maintain image quality), achieving the best possible balance for each specific imaging scenario.
3Area of stationary object
If all projection data is processed for each slice, then complete anatomical coverage is achieved, but processing complexity and computational load increase
Solution Approach 1:
The processing arrangement segments the projection data into distinct sub-ranges based on temporal or angular criteria. This segmentation allows the system to process only the relevant portions of data for each anatomical slice, reducing computational complexity while maintaining complete anatomical coverage through systematic data selection across multiple sub-ranges.
Solution Approach 2:
The invention extracts and selects only the necessary sub-ranges of projection data corresponding to the anatomical phase of interest. By taking out only the essential data portions rather than processing all available data, the system reduces processing complexity and computational load while still achieving the required anatomical coverage for diagnostic purposes.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A method for use in image reconstruction of CT projection data, which aims at reducing motion artefacts in reconstructed images caused by movement of anatomical bodies. Embodiments are based on mitigating motion artefacts based on restricting the range of data that is used for reconstructing each slice. More particularly, a sub-range of the projection data corresponding to each slice is selected, this sub-range being chosen based on determining one or more sub-windows of visibility of a target anatomical object or event within the projection data sequence. The event may be a particular phase of a movement cycle of the anatomical body. The structure could be a particular portion of the anatomical body which is of interest. Either approach leads to reduction of motion artefacts within a single slice, by restricting the data range, and focusing upon the data which is most relevant clinically.