PET–CT Image Registration With Intermediate PET Deformation Fields

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Accurate registration of cardiac PET imaging data to cardiac CT angiography data is challenging due to weak local structural correspondence between functional and anatomical data, especially when using separate scanners with different respiratory and cardiac motion phases.

Innovation Solution

Acquire a first PET image volume with a first radiotracer, followed by a second PET image volume during transit of a second radiotracer bolus, and then register this to a CT angiography image volume, using combined deformation fields to align the images accurately.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If direct registration of PET and CT angiography images is performed, then the registration process is simple, but the registration accuracy is low due to weak local structural correspondence

Engineering Contradiction:

Improveregistration process complexityVSAvoidregistration accuracy

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The patent introduces a second PET image volume acquired during radiotracer bolus transit as an intermediary between the first PET image and CT angiography image. This intermediate image contains both functional information (from the first radiotracer) and anatomical vascular information (from the second radiotracer bolus transit), enabling accurate registration to the CT angiography image while maintaining structural correspondence.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Adaptability or versatility

If separate scanners are used for PET and CT angiography imaging, then the imaging systems are independent and flexible, but the structural correspondence between images is weak

Engineering Contradiction:

Improveimaging system flexibilityVSAvoidstructural correspondence

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The second PET image volume serves as a mediator that bridges the functional PET data and anatomical CT angiography data. By acquiring this intermediate image during bolus transit with the same PET scanner used for the first image, the system maintains independence and flexibility of separate scanners while establishing strong structural correspondence through the vascular anatomy captured during bolus transit.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Loss of information

If multiple radiotracers are administered sequentially, then comprehensive functional and anatomical information is obtained, but the imaging protocol becomes more complex

Engineering Contradiction:

Improvefunctional and anatomical information completenessVSAvoidimaging protocol complexity

Core Design Contradiction:

Loss of informationVSDevice complexity

Solution Approach 1:

The patent implements continuous imaging by acquiring the second PET image volume during the transit of the radiotracer bolus, without interrupting the imaging process. This continuous acquisition approach captures both the functional information from the first radiotracer and the anatomical vascular information from the bolus transit in a seamless manner, reducing protocol complexity compared to separate discrete imaging sessions.

Inventive Principle:

Principle #20Continuity of useful action

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 method enables precise registration of PET and CT angiography images, providing a comprehensive view of vascular structures and plaque sites, enhancing diagnostic accuracy and reducing the need for additional imaging sessions.

Implementation Method 1

positron emission tomography (PET) use various physical principles, such as differential transmission of x-rays through target volume and uptake of one or more radiotracers by different tissue types

Methodology Applied

Scientific EffectRadioactive decay: Radioactive Decay

Implementation Method 2

acquiring a first positron emission tomography (PET) image volume of a patient injected with a first radiotracer

Methodology Applied

Scientific EffectPositron emission: Radioactive Decay

Implementation Method 3

computed tomography (CT) and positron emission tomography (PET) use various physical principles, such as differential transmission of x-rays through target volume

Methodology Applied

Scientific EffectX-ray transmission: X-Ray

Data Source

PatentEP4585155A1Systems and methods for image registration

Publication Date: 2025.07.16 GE PRECISION HEALTHCARE LLC

Figure 1
Figure 2
Figure 3

AI summary

Methods and systems are herein provided for image registration of PET and CT image volumes. In one example, a method comprises acquiring a first positron emission tomography (PET) image volume of a patient injected with a first radiotracer (502), wherein the first PET image volume is acquired with a PET imaging system; acquiring a second PET image volume of the patient with the PET imaging system during transit of a bolus of a second radiotracer (508); acquiring a computed tomography (CT) angiography image volume of the patient (510); registering the first PET image volume to the second PET image volume to generate a first deformation field (512, 516); registering the second PET image volume to the CT angiography image volume to generate a second deformation field (518, 522); generating a final registered image volume based on a combination of the first and second deformation fields (526); and outputting the final registered image volume for display (526).