MRF Dictionary Inner Product Approximation for Reduced Storage

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional magnetic resonance fingerprinting (MRF) dictionaries are excessively large, leading to significant constraints on computational and storage resources, making the process of generating tissue property maps highly resource-intensive.

Innovation Solution

The system and method approximate the inner product as a quadratic function of MRF products, reducing the size of the MRF dictionary and corresponding computational resources, allowing for efficient tissue property mapping by comparing signal evolutions to a reduced dictionary.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional MRF dictionaries are used to ensure accurate tissue property characterization, then measurement precision is improved, but device complexity and computational resources increase significantly

Engineering Contradiction:
Improvetissue property characterization accuracyVSAvoiddictionary size and computational resources
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the tissue property space into discrete grids of T1 and T2 values, creating a structured dictionary where each entry represents a specific tissue property combination. This segmentation allows the system to cover the full range of possible tissue properties while maintaining an organized, manageable structure that can be efficiently searched and processed.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent systematically varies the tissue property parameters (T1 and T2 relaxation times) across the dictionary, creating entries that represent different tissue states. By changing these parameters in a controlled manner across the dictionary grid, the system captures the full range of tissue variability while maintaining a structured format that optimizes both accuracy and computational efficiency.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If larger MRF dictionaries are used to reduce discretization errors, then measurement precision is improved, but loss of time increases due to longer processing durations

Engineering Contradiction:
Improvetissue property mapping accuracyVSAvoidprocessing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent performs preliminary generation of the MRF dictionary with fine discretization before the actual tissue property mapping process. By pre-computing the dictionary with high resolution (fine T1 and T2 steps) and storing it for reuse, the system eliminates the need to recalculate these values during each scanning session, thereby achieving high measurement precision without incurring excessive processing time during clinical use.

Inventive Principle:
Principle #10Preliminary action

3Measurement precision

If fine discretization steps are used in T1 and T2 values, then measurement precision is improved, but device complexity and storage requirements increase

Engineering Contradiction:
Improvetissue property resolutionVSAvoiddictionary storage size
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent segments the continuous T1 and T2 parameter spaces into discrete grids with fine steps (e.g., T1 steps of 10-50ms, T2 steps of 5-10ms). This segmentation creates a manageable set of discrete tissue property combinations that capture the essential variability of tissue properties while avoiding the infinite complexity of continuous parameters, thereby balancing precision with storage feasibility.

Inventive Principle:
Principle #1Segmentation

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 results in improved efficiency and accuracy of tissue property mapping, reducing discrepancies between coarse and fine dictionary matches, and providing faster processing times compared to traditional MRF methods.

Implementation Method 1

a magnetic gradient system including a plurality of magnetic gradient coils configured to apply at least one magnetic gradient field to the polarizing magnetic field

Methodology Applied
Scientific EffectMagnetic gradient field: Magnetic Field

Implementation Method 2

Magnetic resonance fingerprinting ('MRF') is a technology, which is described, as one example, by D. Ma, et al., in 'Magnetic Resonance Fingerprinting,' Nature, 2013; 495(7440):187-192, that allows one to characterize tissue species using nuclear magnetic resonance ('NMR')

Methodology Applied
Scientific EffectMagnetic resonance: Resonance

Data Source

PatentUS11385311B2System and method for improved magnetic resonance fingerprinting using inner product space
Publication Date: 2022.07.12 CASE WESTERN RESERVE UNIV
  • US11385311B2 patent drawing
  • US11385311B2 patent drawing
  • US11385311B2 patent drawing

AI summary

A system and method is provided for improved magnetic resonance fingerprinting (MRF) data dictionary matching using an MRF dictionary having entries with an inner product storing tissue properties.