Premium
Optimized outer volume suppression for single‐shot fast spin‐echo cardiac imaging
Author(s) -
Le Roux Patrick,
Gilles Raymond J.,
McKin Graeme C.,
Carlier Pierre G.
Publication year - 1998
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/jmri.1880080505
Subject(s) - single shot , multislice , computer science , echo (communications protocol) , phase (matter) , encoding (memory) , spin echo , nuclear magnetic resonance , physics , biomedical engineering , algorithm , magnetic resonance imaging , artificial intelligence , optics , medicine , radiology , computer network , quantum mechanics
Among the ultrafast MRI techniques, the single‐shot fast spin‐echo sequence offers a robust alternative to echo planar imaging, essentially because of a much reduced sensitivity to B 0 inhomogeneity. This property is particularly appealing in situations in which B 0 in‐homogeneities can be severe and difficult to correct, such as in cardiac imaging. With single‐shot cardiac imaging, however, achieving high resolution over the necessarily large field of views without introducing back‐folding artifacts is problematic. One option is to use multishot sequences. However, then issues related to cardiac gating arise. Another solution is to use, optimized presaturation slabs with quadratic phase pulses generated by the Shinnar‐LeRoux algorithm. These can be set to reduce the field of view in the phase‐encoding direction, resulting in a reduction in the number of phase‐encoding steps. For instance, for a 1 × 2‐mm spatial resolution, over a rectangular, 250 × 125‐mm field of view, and using a half Fourier acquisition, an echo‐train length of only 40 is required. With a 4.5‐msec echo spacing, the total imaging time is ≈ 180 msec. The efficacy of this solution on phantoms and volunteers is demonstrated. Multislice short‐axis examinations of the whole heart, realized within a single short breath‐hold of ∼ 10 seconds, are shown. The possibility of investigating not only cardiac anatomy but also both contractility and myocardial perfusion is discussed.