Dual Multiple Aperture Devices for Dynamic X-ray Beam Shaping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current CT scanners lack the flexibility to control the spatial distribution of x-ray beams effectively, limiting dose reduction strategies and failing to account for patient size variability during imaging, which is essential for optimizing radiation beam intensity profiles.
Innovation Solution
The use of dual multiple aperture devices with predetermined designs and relative motion, optimized using mathematical and physical models, to generate a predetermined fluence pattern, allowing for dynamic modulation of the x-ray beam and improved beam shaping in x-ray imaging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If static bow-tie filters are used to shape the x-ray beam, then beam intensity distribution is improved, but adaptability to patient size variability is worsened
Solution Approach 1:
The patent applies dynamics by replacing static bow-tie filters with dynamically adjustable aperture devices that can change their transmission pattern in real-time. The aperture devices are controlled to adapt to different patient sizes and anatomical regions, allowing the beam intensity distribution to be optimized for each specific imaging scenario rather than using a fixed static filter design.
Solution Approach 2:
The patent implements parameter changes by varying the transmission characteristics of the aperture devices based on patient parameters such as size, anatomy, and imaging region. The system adjusts aperture positions, shapes, and transmission levels dynamically to match the specific requirements of each patient, thereby resolving the contradiction between maintaining optimal beam shaping and adapting to patient variability.
2Loss of energy
If tube current modulation is used to control exposure, then dose reduction is improved, but spatial distribution control is worsened
Solution Approach 1:
The patent applies segmentation by dividing the x-ray beam into multiple discrete regions using independently controllable aperture devices. Each aperture can be individually adjusted to control the spatial distribution of radiation to different anatomical regions, providing fine-grained control over where radiation is delivered and at what intensity, thereby improving both dose reduction and spatial distribution control.
Solution Approach 2:
The patent introduces aperture devices as intermediary elements between the x-ray source and the patient. These intermediaries actively modulate the beam spatial distribution before it reaches the patient, providing precise control over radiation delivery patterns and enabling region-specific dose optimization that tube current modulation alone cannot achieve.
3Adaptability or versatility
If dynamic fluence field modulation is implemented, then acquisition flexibility is improved, but device complexity is worsened
Solution Approach 1:
The patent implements universality by designing aperture devices that can perform multiple functions: beam shaping, dose modulation, region-of-interest selection, and adaptive filtering. A single multi-functional aperture system replaces what would otherwise require multiple separate components, achieving high acquisition flexibility while managing device complexity through integrated design.
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 enables the generation of a wide range of fluence patterns, reducing radiation dose and improving image quality by dynamically adjusting the x-ray beam distribution based on patient size and position, thereby enhancing the flexibility and efficiency of CT scans.
Implementation Method 1
Each of the multiple aperture devices have a design and each of the multiple aperture devices are configured to have motion relative to others of the multiple aperture devices. The design and the motion of the multiple aperture devices is predetermined to generate a predetermined fluence pattern.
Data Source
AI summary
The present invention is directed to multiple aperture devices (MADs) for beam shaping in x-ray imaging. Two or more of these binary filters can be placed in an x-ray beam in series to permit a large number of x-ray fluence profiles. However, the relationship between particular MAD designs and the achievable fluence patterns is complex. The present invention includes mathematical and physical models that are used within an optimization framework to find optimal MAD designs. Specifically, given a set of target fluence patterns, the present invention finds, for example, a dual MAD design that is a “best fit” in generating the desired fluence patterns. This process provides a solution for both the design of MAD filters as well as the control actuation that is required (relative motion between MADs) that needs to be specified as part of the operation of a MAD-based fluence field modulation system.