Tomosynthesis Rib Suppression via Iterative Edge Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for generating tomographic images of the chest cavity struggle with suppressing rib content while preserving lung and organ image quality, often resulting in ripple artifacts and requiring significant computational resources, which limits diagnostic utility and is not robust enough to handle variations in rib shape and image quality.

Innovation Solution

A method involving a computer system that processes a set of unsegmented projection images by detecting rib features, generating a predictive model, and iteratively refining rib detection to suppress rib content in each projection image, allowing for accurate rib edge identification and subtraction, thereby improving image quality and reducing ripple artifacts.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the projection density is increased to suppress ripple artifacts, then the diagnostic quality of reconstructed images is improved, but the radiation dose and scan time increase

Engineering Contradiction:
Improvediagnostic qualityVSAvoidprojection density
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent applies parameter changes by modifying the projection images through mathematical operations. Specifically, it uses edge detection algorithms to identify rib structures and applies suppression techniques that alter the density parameters of projected images, thereby reducing ripple artifacts without requiring increased physical projection density

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent replaces the mechanical approach of increasing projection density with a computational method. Instead of physically acquiring more projections, it uses image processing algorithms including edge detection, rib identification, and selective suppression to achieve the same diagnostic quality improvement

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Object-affected harmful factors

If low pass filtering is applied to suppress ripple artifacts, then the artifacts are reduced, but the reconstruction becomes blurred and diagnostic utility is limited

Engineering Contradiction:
Improveripple artifactsVSAvoidimage sharpness
Core Design Contradiction:
Object-affected harmful factorsVSMeasurement precision

Solution Approach 1:

The patent applies local quality by selectively suppressing rib structures in specific regions of the projection images while preserving other anatomical structures. The edge detection and rib identification algorithms target only high-contrast rib edges, applying suppression locally rather than globally, thus maintaining image sharpness in non-rib regions while reducing ripple artifacts

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent segments the projection images by identifying and separating rib structures from other anatomical features using edge detection algorithms. This segmentation allows selective processing of rib regions to suppress ripple artifacts while leaving the rest of the image unaffected, preserving overall diagnostic quality

Inventive Principle:
Principle #1Segmentation

3Object-affected harmful factors

If template matching or rib edge detection is used to suppress ribs, then rib visibility is reduced, but the methods are not robust enough to handle variations in rib shape and image quality

Engineering Contradiction:
Improverib visibilityVSAvoidrobustness to variations
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent applies dynamics by using adaptive algorithms that can adjust to variations in rib shape and image quality. The edge detection and rib identification processes are designed to dynamically adapt to different anatomical variations, making the suppression method more robust and reliable across diverse patient populations and imaging conditions

Inventive Principle:
Principle #15Dynamics

Data Source

PatentUS9659390B2Tomosynthesis reconstruction with rib suppression
Publication Date: 2017.05.23 CARESTREAM HEALTH INC
  • US9659390B2 patent drawing
  • US9659390B2 patent drawing
  • US9659390B2 patent drawing

AI summary

A method for rib suppression in a volume chest x-ray image, executed at least in part by a computer captures a first set of unsegmented projection images, each at a corresponding angle, and forms a second set of segmented projection images by detecting rib features in a first projection image to form a first segmented projection image and generating a base model according to the detected rib features for the first projection image. Each of one or more additional projection images from the first set is processed to add members to the second set by a repeated sequence of generating a predictive model; detecting rib features using the predictive model; adjusting the base model according to detected rib features; and correcting rib detection in one or more members of the second set. The volume chest x-ray image is reconstructed according to the segmented projection images and is displayed.