On the Vanishing of the t-term in the Short-Time Expansion of the Diffusion Coefficient for Oscillating Gradients in Diffusion NMR

Demberg K, Nagel AM, Uder M, Kuder TA, Laun FB (2017)

Publication Type: Journal article

Publication year: 2017

Journal

Frontiers in Physics Frontiers Media

Book Volume: 5

Abstract

Nuclear magnetic resonance (NMR) diffusion measurements can be used to probe porous structures or biological tissues by means of the random motion of water molecules. The short-time expansion of the diffusion coefficient in powers of t(1/2), where t is the diffusion time related to the duration of the diffusion-weighting magnetic field gradient profile, is universally connected to structural parameters of the boundaries restricting the diffusive motion. The t(1/2)-term is proportional to the surface to volume ratio. The t-term is related to permeability and curvature. The short time expansion can be measured with two approaches in NMR-based diffusion experiments: First, by the use of diffusion encodings of short total duration and, second, by application of oscillating gradients of long total duration. For oscillating gradients, the inverse of the oscillation frequency becomes the relevant time scale. The purpose of this manuscript is to show that the oscillating gradient approach is blind to the t-term. On the one hand, this prevents fitting of permeability and curvature measures from this term. On the other hand, the t-term does not bias the determination of the t(1/2)-term in experiments.

Authors with CRIS profile

Armin Michael Nagel Professur für metabolische und funktionelle MR-Bildgebung Michael Uder Lehrstuhl für Diagnostische Radiologie Frederik Bernd Laun Professur für quantitative MR-Bildgebung

Involved external institutions

Deutsches Krebsforschungszentrum (DKFZ) DE Germany (DE)

How to cite

APA:

Demberg, K., Nagel, A.M., Uder, M., Kuder, T.A., & Laun, F.B. (2017). On the Vanishing of the t-term in the Short-Time Expansion of the Diffusion Coefficient for Oscillating Gradients in Diffusion NMR. Frontiers in Physics, 5.

MLA:

Demberg, Kerstin, et al. "On the Vanishing of the t-term in the Short-Time Expansion of the Diffusion Coefficient for Oscillating Gradients in Diffusion NMR." Frontiers in Physics 5 (2017).

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