Diffusion MRI: magnetic field inhomogeneities mitigation

Diffusion MRI: magnetic field inhomogeneities mitigation

Peer-reviewed article not indexed in WoS or Scopus

The article reports on certain artifacts that emerge during the in vitro diffusion-weighted imaging of physical samples. In this context, the authors analyze the influence of magnetic field inhomogeneity, temperature, or eddy currents and consider procedures to mitigation of the artifacts. A technique reducing the examined spurious effects was designed, experimentally verified, and denominated as the three measurements method. The technique proved to be useful mainly for the evaluation of a DWI image measured with a diffusion gradient in the z axis, where the relative measurement error decreased to 3.38% (during measurement using two images, the relative error was greater than 19%). For small errors within the measurement of diffusion constants of a deionised water sample (<5%) it is necessary to select a b-factor value larger than 200x10^6 s.m-2. Temperature stabilisation with an accuracy better than 0.1 degree of celsius during the entire measuring process is a necessary prerequisite for the measurement of biological or material samples with a relative accuracy lower than 1%.

The article reports on certain artifacts that emerge during the in vitro diffusion-weighted imaging of physical samples. In this context, the authors analyze the influence of magnetic field inhomogeneity, temperature, or eddy currents and consider procedures to mitigation of the artifacts. A technique reducing the examined spurious effects was designed, experimentally verified, and denominated as the three measurements method. The technique proved to be useful mainly for the evaluation of a DWI image measured with a diffusion gradient in the z axis, where the relative measurement error decreased to 3.38% (during measurement using two images, the relative error was greater than 19%). For small errors within the measurement of diffusion constants of a deionised water sample (<5%) it is necessary to select a b-factor value larger than 200x10^6 s.m-2. Temperature stabilisation with an accuracy better than 0.1 degree of celsius during the entire measuring process is a necessary prerequisite for the measurement of biological or material samples with a relative accuracy lower than 1%.

correction, diffusion, inhomogeneity, eddy currents, magnetic resonance

correction, diffusion, inhomogeneity, eddy currents, magnetic resonance

MARCOŇ, P.; BARTUŠEK, K.; GESCHEIDTOVÁ, E.; DOKOUPIL, Z.

2013

17.09.2012

Versita Open, Versita Ltd. London

London, Great Britain

1335-8871

Measurement Science Review

12

5

Slovak Republic

205

212

8

http://www.measurement.sk/2012/Marcon.pdf