PET Image Reconstruction Using Autocorrelation Feature Images

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Low-count PET image reconstruction in PET imaging technology results in high noise and low signal-to-noise ratio, making it challenging for clinical applications due to the ill-conditioned inverse estimation problem.

Innovation Solution

The method involves acquiring a prior image with an anatomical image and an autocorrelation feature image determined by a gray-level co-occurrence matrix, and using these features with an iterative algorithm to reconstruct the PET image, improving the signal-to-noise ratio and accuracy of tumor image reconstruction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of time

If low-count PET projection data is used for reconstruction, then injection dose of radiotracer and scan time are reduced, but the reconstructed image quality deteriorates with high noise and low signal-to-noise ratio

Engineering Contradiction:
Improvescan timeVSAvoidimage quality
Core Design Contradiction:
Loss of timeVSMeasurement precision

Solution Approach 1:

The patent applies preliminary action by pre-calculating and storing autocorrelation feature images and their corresponding feature values from high-count PET data before the actual low-count reconstruction process. These pre-computed features serve as prior information that guides the reconstruction of low-count data, eliminating the need to perform complex autocorrelation calculations during the reconstruction phase itself.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces autocorrelation feature images and their feature values as intermediary elements that mediate between the low-count projection data and the final reconstructed image. These intermediaries encode spatial and textural prior information that helps constrain the ill-posed inverse estimation problem, enabling quality reconstruction from limited data without requiring high injection doses or long scan times.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Loss of substance

If low-count PET projection data is used for reconstruction, then economic cost is reduced, but the reconstructed image quality deteriorates with high noise

Engineering Contradiction:
Improveinjection dose of radiotracerVSAvoidsignal-to-noise ratio
Core Design Contradiction:
Loss of substanceVSMeasurement precision

Solution Approach 1:

The patent pre-computes autocorrelation feature images and extracts their feature values from reference high-count PET data before the low-count reconstruction process. This preliminary action creates a library of prior information that can be applied during low-count reconstruction, allowing the system to achieve acceptable image quality with reduced radiotracer injection doses by leveraging pre-analyzed spatial and textural patterns.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The autocorrelation feature values serve as intermediary parameters that bridge the gap between low-count projection data and high-quality reconstructed images. These intermediaries encapsulate prior knowledge about tissue autocorrelation patterns, enabling the reconstruction algorithm to distinguish signal from noise even when the input data has poor signal-to-noise ratio due to low radiotracer doses.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Device complexity

If traditional reconstruction methods are used on low-count data, then the reconstruction process is simple, but the reconstructed image has poor quality and high noise

Engineering Contradiction:
Improvereconstruction algorithm complexityVSAvoidimage quality
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent performs the computationally intensive autocorrelation calculation and feature extraction in advance, before the actual reconstruction process. This preliminary action separates the complex prior information generation from the reconstruction step itself, allowing the reconstruction algorithm to use pre-computed autocorrelation feature values as constraints, thereby maintaining relative simplicity in the reconstruction phase while achieving superior image quality.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces autocorrelation feature values as intermediary constraints in the reconstruction objective function. These intermediaries provide additional information about the expected autocorrelation structure of the image, guiding the reconstruction algorithm to produce higher quality images from low-count data without requiring excessively complex reconstruction methodologies.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentUS12020351B2Method, device and equipment for reconstructing PET images
Publication Date: 2024.06.25 SHENZHEN INST OF ADVANCED TECH
  • US12020351B2 patent drawing
  • US12020351B2 patent drawing
  • US12020351B2 patent drawing

AI summary

A method, device and equipment for reconstructing a PET image are provided. The method includes acquiring a prior image comprising an anatomical image and an autocorrelation feature image, the autocorrelation feature image being determined based on gray-level co-occurrence matrix of the anatomical image; and acquiring a feature value of the prior image; reconstructing the PET image according to the feature value and an iterative algorithm.