MR Control Sequence Optimization for Gradient Coil Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Magnetic resonance (MR) control sequences in MR devices often require inefficient use of gradient coils, leading to longer examination times and limitations in breath-hold and heartbeat-sensitive examinations, particularly in thoracic and cardiological imaging.
Innovation Solution
The method optimizes MR control sequences by dividing them into modules with optimized excitation and phase encoding, taking into account the usage time of gradient coils between excitation and readout modules, allowing for more efficient use of gradient coils and reduced examination time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of moving object
If a rapid succession of excitation pulses, gradient pulses and readout windows is used, then the duration of the MR control sequence is reduced and image data quality is improved, but the gradient coil usage becomes inefficient and examination time increases
Solution Approach 1:
The patent applies dynamics by making the gradient coil usage adaptive rather than static. The system dynamically adjusts gradient pulse parameters based on real-time optimization of the MR control sequence, allowing the gradient coils to be used more efficiently during the rapid succession of pulses while maintaining the reduced duration benefit.
Solution Approach 2:
The patent changes parameters of the gradient pulses and excitation pulses to optimize the overall sequence. By adjusting timing, amplitude, and duration parameters of gradient pulses in coordination with excitation pulses, the system achieves both reduced sequence duration and improved gradient coil efficiency simultaneously.
2Measurement precision
If gradient pulses are applied with high amplitude for rapid data acquisition, then temporal resolution is improved, but the usage time of gradient coils increases leading to longer examination times
Solution Approach 1:
The patent ensures continuous useful action by optimizing the MR control sequence to minimize idle time between gradient pulse applications. The rapid succession of excitation pulses and gradient pulses is coordinated to maintain continuous data acquisition, improving temporal resolution while reducing total examination time through efficient use of gradient coil capacity.
Solution Approach 2:
The patent employs periodic action through the structured repetition of optimized pulse sequences. By organizing gradient pulses and excitation pulses in periodic, coordinated patterns with optimized timing, the system achieves high temporal resolution through rapid periodic sampling while managing overall examination duration through efficient cycle design.
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 optimization results in shorter MR control sequences, reducing the need for breath-holding and improving temporal resolution, especially in applications with fluctuating gradient coil usage, such as asymmetric echoes and three-dimensional measurements.
Implementation Method 1
the body of an examination subject that is to be examined, in particular the body of a patient, is typically exposed to a relatively high main magnetic field, of 1.5 or 3 or 7 tesla for example, with the aid of a main magnet
Implementation Method 2
High-frequency radiofrequency pulses, for example excitation pulses, are then transmitted by means of suitable antenna devices via a radiofrequency antenna unit, which results in the nuclear spins of certain atoms excited into resonance by means of said radiofrequency pulses being tipped through a defined flip angle relative to the magnetic field lines of the main magnet field
Implementation Method 3
In addition, gradient pulses are applied with the aid of a gradient coil unit
Implementation Method 4
During the relaxation of the nuclear spins, radiofrequency signals, referred to as magnetic resonance signals, are emitted, received by means of suitable radiofrequency antennas and then processed further
Data Source
AI summary
Method for optimizing an MR control sequence for acquiring MR data of an examination subject by means of an MR device having gradient coils. The method includes providing an MR control sequence having sequence portions, each having an excitation portion, a phase encoding portion and a readout portion, wherein the phase encoding portion is arranged in each case between the excitation portion and the readout portion with respect to time; providing a defined parameter for the MR control sequence; providing an optimization objective; ascertaining usage time of the gradient coils between the excitation portion and the readout portion with respect to time for each of the sequence portions; optimizing the excitation portions for each of the sequence portions considering the ascertained usage time for the corresponding sequence portion and the defined parameter with regard to the optimization objective; and providing the optimized MR control sequence having the optimized excitation portions.