Simulations of DESIRE Effect for NMR Microscopy

Abstract

Abstract:

Within an advisable measurement time, the signal-to-noise ratio (SNR) is a major limitation of nuclear magnetic resonance microscopy at the spatial resolution of micrometers level. In previous reports, computer simulations showed the “Diffusion Enhancement of Signal and Resolution” (DESIRE) effect may provide potential signal enhancement of one order in one-dimensional case. However, the timeconsuming calculations such as iterative matrix multiplications and finite-differential (FD) methods were utilized for simulating the external magnetic fields and diffusion propagations. In this work, we proposed to use the Shinnar-LeRoux (SLR) algorithm and convolution based diffusion method to accelerate the simulations. Therefore, extensive simulations can be conducted for optimization of pulse sequence. Considering the enhance rate and effective resolution in one dimensional DESIRE experiment, the simulated results indicated the pulse shape of Sinc3 with optimal parameters could achieve superior performance under practical experimental settings.

Key words: nuclear magnetic resonance microscopy, DESIRE effect, computer simulation

CLC Number:

O482.53

CHANG Chia-Hao, WANG Fu-Nien. Simulations of DESIRE Effect for NMR Microscopy[J]. Chinese Journal of Magnetic Resonance, 2010, 27(3): 396-408.

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