MRI Gradient Pulse Optimization via Periodic Curve Reuse
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The generation of eddy currents and subsequent acoustic noise in magnetic resonance apparatuses increases with higher gradient amplitudes and slew rates, requiring time-consuming optimization of gradient pulses to minimize noise exposure.
Innovation Solution
A method for accelerating the progression of a repeating pulse sequence by determining an optimized gradient curve quickly, utilizing periodicity to reuse previously calculated curves and reducing computing power, with spline interpolation and storage of boundary conditions and optimized curves for fast access and calculation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If gradient amplitudes and slew rates are increased to improve imaging speed and resolution, then image quality and examination efficiency are improved, but eddy current generation and acoustic noise increase
Solution Approach 1:
The patent optimizes gradient pulse parameters (amplitude, duration, shape) to achieve the desired imaging performance while minimizing eddy current generation. By carefully selecting and adjusting gradient parameters, the system maintains high imaging speed while reducing the harmful effects of eddy currents and associated acoustic noise.
Solution Approach 2:
The patent employs dynamic optimization of gradient curves, where the gradient waveform is continuously adjusted during the pulse sequence progression. This dynamic approach allows the system to adapt gradient amplitudes and slew rates in real-time, balancing imaging performance requirements with noise reduction goals.
2Object-generated harmful factors
If optimized gradient curves are calculated for every single gradient pulse to minimize noise, then acoustic noise exposure is reduced, but calculation time increases significantly
Solution Approach 1:
The patent exploits the periodic nature of repeating pulse sequences by calculating optimized gradient curves only for unique gradient pulses within a period. Once optimized, these curves are reused in subsequent repetitions of the pulse sequence, dramatically reducing calculation time while maintaining noise minimization benefits across all gradient pulses.
Solution Approach 2:
The patent creates and stores optimized gradient curve templates for unique gradient pulses. These optimized curves are then copied and applied to identical gradient pulses in subsequent pulse sequence repetitions, eliminating the need to recalculate optimization for every single gradient pulse and significantly reducing computational burden.
3Manufacturing precision
If complicated calculations are performed to determine optimized gradient curves, then gradient pulse optimization quality is improved, but computing power requirements and processing time increase
Solution Approach 1:
The patent performs gradient curve optimization calculations in advance, before the actual pulse sequence execution. By pre-calculating and storing optimized gradient curves for all unique gradient pulses in a pulse sequence period, the system eliminates the need for complex real-time calculations during imaging, reducing computing power requirements while maintaining optimization quality.
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 calculation time and noise development, enabling real-time feature implementation and use of less powerful computers, while maintaining optimized gradient curves for reduced noise exposure.
Implementation Method 1
a gradient system (16) for applying a magnetic field gradient
Implementation Method 2
a radio-frequency transmission system (17) for emitting excitation signals (radio-frequency pulses)
Implementation Method 3
nuclear spins of atoms excited to resonance are deflected (flipped) by a defined flip angle relative to the magnetic field lines of the basic magnetic field. Upon a subsequent relaxation of the nuclear spins, radio-frequency signals (known as magnetic resonance signals) are radiated
Implementation Method 4
the generation of eddy currents in conductive components of the apparatus increases with increasing gradient amplitudes and/or slew rates, and these eddy currents contribute to the generation of Lorentz forces that acoustic noise exposure also increases
Implementation Method 5
these eddy currents contribute to the generation of Lorentz forces that acoustic noise exposure also increases
Data Source
AI summary
In a method for an accelerated progression of a repeating pulse sequence with an optimized gradient curve (that has at least one pulse) for a magnetic resonance examination by operation of a magnetic resonance apparatus, boundary conditions for a first gradient pulse of a first progression of the pulse sequence are detected, and the boundary conditions of the first gradient pulse of the first progression of the pulse sequence are compared with boundary conditions of a previous gradient pulse of a previous progression of the pulse sequence. An optimized gradient curve of the first gradient pulse of the first progression of the pulse sequence is determined from the gradient curve of the previous gradient pulse when agreement of the boundary conditions of the first gradient pulse with the boundary conditions of the previous gradient pulse exists.