MRI method of diffusion measurement in heterogeneous materials

článek v časopise ve Web of Science, Jimp

angličtina

he paper describes a newly proposed magnetic resonance (MR) method and the processing of signals being measured, with the aim of establishing the diffusion coefficients in heterogeneous materials. The pulsed field gradient stimulated-echo methods have reduced coupling between the applied magnetic field gradient and a constant internal magnetic field gradient caused by different susceptibilities throughout the sample. When studying systems where it is necessary to keep the duration of the pulse sequence at a minimum or to study diffusion as a function of observation time, the spin-echo method should be chosen. The basic idea is to acquire the spin echo amplitude with pulsed field gradient of opposite signs and to add/subtract the NMR signals measured in a suitable way. The measuring method and the digital signal processing enable eliminating the effect of static magnetic field on the accuracy of measuring. The method proposed can be used to measure diffusion-weighted images of liquids found in porous materials, and in the development of new MR tomography measuring methods in the Institute of Scientific Instruments of the Academy of Sciences of the Czech Republic, v.v.i.

Diffusion measurement, diffusion coefficients, nuclear magnetic resonance, heterogeneous systems, diffusion-weighted image.

BARTUŠEK, K.; GESCHEIDTOVÁ, E.

2008

13. 3. 2008

IOP Publishing

UK

0957-0233

Measurement Science and Technology

19

1

Spojené království Velké Británie a Severního Irska

1

8

8