NMR Signal Fitting via Echo Spacing Adjustment

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The D-T2 two-dimensional spectral analysis method in nuclear magnetic resonance (NMR) systems requires collecting a large amount of data, leading to long collection times, high hardware requirements, and unstable fitting results due to sensitivity to noise and poor robustness of the algorithm.

Innovation Solution

The method involves acquiring a plurality of echo signals with varying echo spacing, processing them to obtain signals with transverse relaxation and diffusion attenuation, and fitting these signals using a Carr-Purcell-Meiboom-Gill (CPMG) sequence in combination with prior knowledge to obtain diffusion coefficients, transverse relaxation times, and content weights, with a unilateral magnet performing diffusion encoding and adjusting echo spacing to satisfy specific b-value conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If D-T2 two-dimensional spectral analysis method is used to measure substance components, then measurement precision is improved, but collection time increases and data storage requirements increase

Engineering Contradiction:

Improvesubstance component measurement precisionVSAvoiddata collection time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent changes the measurement parameters by using a simplified one-dimensional spectral analysis approach with optimized echo spacing parameters, rather than the traditional two-dimensional D-T2 spectral analysis. This parameter change reduces the complexity of data acquisition while maintaining measurement capability for substance components.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent extracts only the essential measurement information needed for substance component analysis, eliminating the need for comprehensive two-dimensional spectral data. By taking out only the critical one-dimensional spectral data with optimized echo spacing, the method reduces data collection time and storage requirements while preserving measurement precision.

Inventive Principle:

Principle #2Taking out (Extraction)

2Measurement precision

If D-T2 two-dimensional spectral analysis method is used, then measurement precision is improved, but device complexity increases

Engineering Contradiction:

Improvesubstance component measurement precisionVSAvoidhardware requirements

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

Inventive Principle:

Principle #35Parameter changes

3Measurement precision

If traditional spectral analysis algorithms are used, then measurement precision is improved, but algorithm robustness deteriorates due to noise sensitivity

Engineering Contradiction:

Improvefitting result precisionVSAvoidalgorithm robustness

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent applies preliminary signal processing and optimization before the main spectral analysis step. By pre-optimizing the echo spacing parameters and preparing the signal data in advance, the method reduces the impact of noise on the fitting algorithm, thereby improving both precision and robustness.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent incorporates feedback mechanisms in the spectral analysis process, where the fitting results are continuously refined by comparing with expected patterns and adjusting parameters accordingly. This feedback loop reduces sensitivity to noise and improves the reliability of the fitting results.

Inventive Principle:

Principle #23Feedback

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 reduces the need for extensive data collection, lowers data processing time, and enhances the stability and robustness of the fitting results, allowing for efficient substance analysis and clinical diagnosis with shorter acquisition times and lower storage requirements.

Implementation Method 1

a natural gradient magnetic field formed by the unilateral magnet is configured to perform diffusion encoding on the plurality of signals varying in transverse relaxation and diffusion attenuation

Methodology Applied

Scientific EffectDiffusion encoding: Diffusion

Implementation Method 2

the transverse magnetization intensity Mxy decays over time. After the action of 90° pulse, Mxy satisfies formula (1): Mxy(t)=Mxymaxe−t/T2

Methodology Applied

Scientific EffectTransverse relaxation: Stress Relaxation

Implementation Method 3

the diffusion movement of water molecules in the direction of the gradient magnetic field will attenuate the NMR signal

Methodology Applied

Scientific EffectDiffusion: Diffusion

Data Source

PatentUS11766189B2Nuclear magnetic resonance system-based substance measurement method and system

Publication Date: 2023.09.26 MARVEL STONE HEALTHCARE CO LTD

AI summary

A nuclear magnetic resonance (NMR) system-based substance measurement method, including: acquiring several echo signals of an NMR pulse sequence varying in echo spacing from a substance to be measured followed by processing to obtain several signals varying in transverse relaxation and diffusion attenuation; and fitting, in combination with the prior knowledge, the signals to obtain the diffusion coefficient, transverse relaxation time or/and content weight of individual components of the substance to be measured. This application further provides a substance measurement system including a console, a magnet module, and an NMR system.