Method for Computing Optimal Diffusion Encoding Gradient Waveforms for MRI

摘要

A method of obtaining analytical expressions for an optimized diffusion encoding gradient (DEG) waveform is disclosed. The method uses a constrained numerical optimization to obtain an optimal configuration of a DEG waveform. The optimization adjusts parameters for a waveform modeled as a finite set of square pulses to maximize an exact b-value equation, while maintaining a waveform shape that also compensates for motion. The optimal configuration is then verified using a waveform model of a set of trapezoidal pulses to obtain an optimal DEG waveform. Generally, the parameters describing the reduced set of trapezoidal pulses are reduced, thereby allowing the optimal DEG waveform to be expressed as closed-form analytical expressions. The analytical expressions simplify the derivation of optimal DEG waveforms for a range of diffusion imaging scanning parameters, thereby improving the quality and versatility of diffusion weighted MRI.