<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p> 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 artifact mitigation procedures. A technique reducing the examined spurious effects was designed, experimentally verified, and denominated as the three measurement method. The technique proved to be useful mainly for the evaluation of a DWI image measured with a diffusion gradient in the <italic>z </italic>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 deionized water sample (&lt; 5 %) it was necessary to select a <italic>b</italic>-factor value larger than 200·106 s.m-2. Temperature stabilization with accuracy better than 0.1 °C during the entire measuring process is a necessary prerequisite for the measurement of biological or material samples with relative accuracy lower than 1 %.</p></abstract>

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 artifact mitigation procedures. A technique reducing the examined spurious effects was designed, experimentally verified, and denominated as the three measurement 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 deionized water sample (< 5 %) it was necessary to select a b-factor value larger than 200·106 s.m-2. Temperature stabilization with accuracy better than 0.1 °C during the entire measuring process is a necessary prerequisite for the measurement of biological or material samples with relative accuracy lower than 1 %.

Diffusion MRI: mitigation of magnetic field inhomogeneities

Department of Theoretical and Experimental Electrical Engineering, Faculty of Electrical Engineering and Communication, Brno University of Technology, Kolejni, 2906/4., 612 00, Brno, Czech Republic

Institute of Scientific Instruments of the ASCR v.v.i., Kralovopolska, 147, 612 00, Brno, Czech Republic

Measurement Science Review

{"article-title":"Diffusion MRI: mitigation of magnetic field inhomogeneities"}

The article reports on certain artifacts that emerge during the in vitro diffusion-weighted imaging of physical samples. In this context, the authors analyze...

Diffusion MRI: mitigation of magnetic field inhomogeneities

Publié en ligne: 21 oct. 2012

Pages: 205 - 212

DOI: https://doi.org/10.2478/v10048-012-0031-8

This content is open access.