Stray field (STRAFI) and single point (SPI) magnetic resonance imaging

Abstract

The ability of magnetic resonance imaging (MRI) to examine nondestructively and non-invasively dynamic changes in a vast range of systems has made MRI a major analytical tool in many scientific disciplines. However, one of the main drawbacks to its even wider acceptance, particularly in materials science, has been the difficulty of recording signals from samples containing nuclei with very short spin relaxation times. Stray field imaging (STRAFI) and single point imaging (SPI) not only overcome this difficulty, but can be applied with relatively modest changes to existing, commercially available NMR spectrometers. ‘Solid state’ MRI is therefore no longer the province solely of specialist NMR laboratories. This chapter contains a brief overview of the theory and methodology of STRAFI and SPI imaging, and reviews the literature to date that describes the already successful applications of the techniques. As with ‘liquid’ MRI, these emanate from a wide range of disciplines and demonstrate the versatility of these imaging modalities.