guest ::
| Home > Publications database > CHAPTER 1. Introduction to Magnetic Resonance Imaging |
| Home > Publications database > CHAPTER 1. Introduction to Magnetic Resonance Imaging |
| Contribution to a book | FZJ-2018-07749 |
;
2018
Royal Society of Chemistry
Cambridge
This record in other databases:
Please use a persistent id in citations: doi:10.1039/9781788013062-00001
Abstract: Nuclear magnetic resonance (NMR) is the technique that underpins magnetic resonance imaging (MRI) in its application in diagnostic medical imaging. Spin dynamics in NMR are described using a semi-classical model resulting in a net magnetisation, which is amenable to manipulation using radiofrequency pulses. The introduction of a spatially varying magnetic field, the magnetic field gradient, in the three orthogonal directions is introduced and it is shown how the application of gradients enables the selection of a physical slice and encoding of the two remaining in-plane dimensions. The concept of image encoding is then extended to 3D imaging. Beginning with a simple classical spin model, it is shown how the phenomenological Bloch equations can be derived and solved under the influence of particular field configurations. Eventually, the Bloch equations lead to the so-called signal equation and the introduction of the concept of a reciprocal space, the k-space, which is linked to real space by the Fourier transform (FT). Image reconstruction techniques going beyond the FT are also briefly touched upon to give the reader a fuller appreciation of modern, state-of-the-art MRI. In-plane acceleration methods operating both in k-space and in real space are described, as are multi-band acceleration techniques, which enable the acquisition of multiple slices simultaneously. Finally, a classification scheme, albeit a simple and incomplete one, is presented to enable the novice reader to gain an understanding of how order can be brought into the world of MRI pulse sequences
|
The record appears in these collections: |
Files
PDF