Tomographic Image Artifact Reduction via Area Interpolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional radiation tomographic image generation techniques, such as Filtered Back Projection (FBP) and Likelihood Expectation Maximization (ML-EM), often produce artifacts near high-density substances like metal in tomographic images, while methods that reduce artifacts, like Shift Addition, compromise spatial resolution.
Innovation Solution
A radiation tomographic image generating method that separates images of extraneous substances from the area of interest, interpolates missing data from peripheral regions, generates interpolation images, and synthesizes tomographic images using both original and interpolated data to reduce artifacts while maintaining high spatial resolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If Filtered Back Projection (FBP) method or Likelihood Expectation Maximization (ML-EM) method is used for tomographic image generation, then the spatial resolution is improved, but artifacts appear adjacent to high-density substances like metal
Solution Approach 1:
The patent segments the tomographic image generation process into multiple steps: first generating a preliminary image using FBP or ML-EM, then identifying artifact regions adjacent to high-density substances, and finally processing these regions separately to remove artifacts while preserving the high spatial resolution achieved by the initial reconstruction
Solution Approach 2:
The patent extracts and removes artifacts from the tomographic image by identifying regions adjacent to high-density substances and applying specific processing to eliminate the harmful artifacts while maintaining the beneficial high spatial resolution characteristics of the original reconstruction method
2Object-generated harmful factors
If Shift Addition method is used to inhibit artifacts adjacent to metal, then artifacts are reduced, but spatial resolution becomes inferior
Solution Approach 1:
The patent merges the advantages of different methods by combining the artifact-reduction capability of Shift Addition with the high spatial resolution of FBP or ML-EM. The process applies Shift Addition principles specifically to artifact-prone regions while maintaining the superior resolution characteristics of FBP/ML-EM in the overall image
Solution Approach 2:
The patent applies different processing qualities to different regions of the image: using artifact-reduction techniques specifically in regions adjacent to high-density substances while maintaining the original high-resolution reconstruction characteristics in other regions, thus achieving local optimization without global compromise
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
The method effectively reduces artifacts near high-density substances, allowing clear observation of the area of interest by generating tomographic images with improved spatial resolution and clear boundaries between extraneous and other areas.
Implementation Method 1
an area interpolation step for generating interpolation images by interpolating an area of the extraneous substance, from peripheral regions thereof, in the images of the extraneous substance extracted and separated in the extraction separation step
Implementation Method 2
an extraneous projection data generating step for generating extraneous projection data which is projection data of the extraneous substance, from differences between the acquired radiological images and the interpolation images
Data Source
AI summary
An area of an extraneous substance (e.g. area of metal or the like) in images (pre-interpolation projection data in the embodiment) of the extraneous substance (e.g. high-density substance such as metal) extracted and separated by extraction separation in step S1 is interpolated by area interpolation in step S2. Therefore, artifacts can be reduced, while maintaining high spatial resolution, if tomographic images (first tomographic images in the embodiment) are generated by first tomographic image generation in step S3 from the interpolation images interpolated and generated (post-interpolating projection data in the embodiment).