Dynamic Gradient Delay Compensation in MR Scanning Sequences
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for compensating gradient delays in magnetic resonance (MR) scanning sequences fail to account for varying gradient amplitudes, leading to image quality loss and artifacts, especially in precise scanning techniques like echo planar imaging (EPI) and ultra-short echo time sequences.
Innovation Solution
A method and apparatus that determine the current gradient amplitude and use a mapping or fitting relationship between gradient delay and amplitude to calculate and compensate for the current gradient delay, ensuring accurate emission of the MR scanning sequence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If fixed gradient delay compensation is performed using an average value, then the device complexity is reduced and ease of operation is improved, but manufacturing precision and measurement precision deteriorate due to inability to account for varying gradient amplitudes
Solution Approach 1:
The patent applies dynamics by transitioning from fixed gradient delay compensation to dynamic gradient delay compensation that adapts to varying gradient amplitudes. The system now determines gradient delay based on the actual gradient amplitude being used, allowing the compensation value to change dynamically with different scanning parameters, thus maintaining precision across varying operating conditions
Solution Approach 2:
The patent implements parameter changes by using multiple gradient delay values corresponding to different gradient amplitude ranges. Instead of using a single average value, the system selects or calculates the appropriate gradient delay compensation value based on the current gradient amplitude parameter, thereby maintaining measurement precision while adapting to different operational states
2Device complexity
If gradient delay compensation is performed without considering gradient amplitude variations, then device complexity is reduced, but reliability deteriorates due to image quality loss and artifacts in precise scanning sequences
Solution Approach 1:
The system transitions from static to dynamic gradient delay compensation by determining the appropriate compensation value based on the actual gradient amplitude. This dynamic approach ensures reliable scanning results across different sequence types and amplitude settings without requiring overly complex hardware modifications
Solution Approach 2:
The patent changes the compensation parameter selection from a fixed average value to amplitude-dependent values. By storing multiple gradient delay values and selecting based on the current gradient amplitude range, the system maintains high reliability for EPI and ultra-short echo time sequences while keeping the implementation manageable
3Measurement precision
If multiple gradient delays are measured at different gradient amplitudes, then measurement precision is improved, but device complexity increases due to need for mapping and fitting relationships
Solution Approach 1:
The system uses dynamic selection of gradient delay values based on measured amplitude-dependent delays. By establishing mapping relationships between gradient amplitudes and their corresponding delays, the system achieves high measurement precision while managing complexity through systematic organization of multiple delay values
Solution Approach 2:
The patent measures and stores multiple gradient delay values at different gradient amplitudes, then uses parameter changes to select the appropriate delay value based on the current amplitude. This approach maintains high measurement precision by accounting for amplitude variations while managing system complexity through structured parameter storage and selection
Data Source
AI summary
In a method and MR scanning apparatus for compensating for gradient delay in the MR scanning sequence, a current gradient amplitude of the MR scanning sequence is determined. Based on the current gradient amplitude and a mapping between gradient delay and gradient amplitude, a current gradient delay corresponding to the current gradient amplitude is determined. The gradient delay in the MR scanning sequence is compensated according to the current gradient delay.