Weighted iterative inversion method for T₂ spectrum in nuclear magnetic resonance

Abstract

In traditional nuclear magnetic resonance T₂ inversion methods, the components with long T₂ absorb the components with short T₂, especially for low magnetic field intensity. As a result, the true distribution of all components often cannot be reflected by their solutions, and thus obtaining short T₂ components is an important T₂ inversion problem. Herein, a weighted iterative inversion method for T₂ spectrum in nuclear magnetic resonance is proposed to solve this problem. The weight-based method is applied to ensure that the short T₂ components are not eliminated. The weight scheme is determined by two parameters: the number of weights and maximum weight. The number of weights is determined by the rate of decay, and the maximum weight is mainly determined by three parameters: signal-noise ratio, curvature, and slope of collected signal. To avoid the mutations of results caused by weights, the iteration process was adopted to obtain the optimal solution. The proposed method provides good results, and it was verified to be robust and accurate though simulations and experiments.

Keywords:

• Nuclear magnetic resonance
• T2 inversion
• T2 spectra
• weighted iterative inversion

Additional information

Funding

This work was supported by National Key Scientific Instrument and Equipment Development Projects of China [Grant. 2013YQ170463], Innovation Program of Shanghai Municipal Education Commission [No. 14ZZ135].