Premium
New method for contrast manipulation in DNP‐enhanced MRI
Author(s) -
Planinšič Gorazd,
Grucker Daniel,
Stepišnik Janez
Publication year - 1996
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.1910350316
Subject(s) - nuclear magnetic resonance , magnetic field , magnetic resonance imaging , subtraction , physics of magnetic resonance imaging , magnetization , physics , spin echo , polarization (electrochemistry) , pulsed epr , amplitude , magnetic resonance force microscopy , materials science , magnetic resonance microscopy , chemistry , optics , ferromagnetic resonance , mathematics , radiology , medicine , arithmetic , quantum mechanics
The magnetization subtraction technique (MS), which is equivalent to the inversion recovery technique in strong magnetic fields, has been implemented in dynamic nuclear polarization‐enhanced magnetic resonance imaging (DNPI). The general theoretical basis of the MS method, which can be applied to DNPI or to prepolarized MRI in weak magnetic fields (such as Earth's magnetic field), is introduced. Details are provided about the signal amplitude, dynamic range of the method, and conditions required to observe signal void in samples with specific T 1 relaxation times. The experimental results obtained with MS DNPI are presented and discussed. In the experiments, electron spin resonance irradiation frequencies of 199 MHz and 16.2 MHz were employed. Also, T 1 contrast manipulation in the polarizing and in the detection magnetic field is discussed and demonstrated for MS DNPI.