In porous media, magnetic susceptibility differences between the solid phase and the fluid filling the pore space lead to field inhomogeneities inside the pore space. In many cases, diffusion of the spins in the fluid phase through these internal inhomogeneities controls the transverse decay rate of
Susceptibility effects in porous media in the presence of flow
β Scribed by Min-Ying Su; Orhan Nalcioglu
- Publisher
- John Wiley and Sons
- Year
- 1993
- Tongue
- English
- Weight
- 624 KB
- Volume
- 3
- Category
- Article
- ISSN
- 1053-1807
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
Magnetic resonance (MR) imaging of microvascular flow is an important topic in biomedicine because it permits access to the functional state of a biologic system. The internal heterogeneous magnetic field due to susceptibility differences within tissues is one of the factors that can affect signal intensity. A glass bead phantom simulating a porous medium was used to experimentally study the effect of the internal magnetic field on MR flow measurements. A physical model was developed to simulate the paths of the moving spins and the local magnetic field distribution in the medium to estimate the signal intensity with spinβphase analysis. The susceptibility variation inside the glass bead phantom was estimated by comparing the simulation results with the experimental data. Experiments were also performed with a tissueβsimulating phantom, and the results indicated that the effect of the internal field inhomogeneity on in vivo microvascular flow measurements was negligible.
π SIMILAR VOLUMES
The effect of small surface tension on a class of axisymmetric flows with suction is studied numerically. The dynamic evolution of a blob of incompressible viscous fluid, surrounded by air and drawn into an interior sink, is considered. The velocity field of the viscous fluid is assumed to satisfy D
A pore-level network model has been developed to study the effect of spreading coefficients on three-phase flow through porous media. This model combines the morphological description of the pore space with pore-level displacement physics to model capillarity-controlled, immiscible gas invasion of a