B1-insensitive T2 preparation for improved coronary magnetic resonance angiography at 3 T.
Détails
ID Serval
serval:BIB_7CEAEE6CBFF9
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
B1-insensitive T2 preparation for improved coronary magnetic resonance angiography at 3 T.
Périodique
Magnetic Resonance In Medicine
ISSN
0740-3194[print], 0740-3194[linking]
Statut éditorial
Publié
Date de publication
2006
Volume
55
Numéro
4
Pages
858-864
Langue
anglais
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Publication Status: ppublish
Résumé
At 3 T, the effective wavelength of the RF field is comparable to the dimension of the human body, resulting in B1 standing wave effects and extra variations in phase. This effect is accompanied by an increase in B0 field inhomogeneity compared to 1.5 T. This combination results in nonuniform magnetization preparation by the composite MLEV weighted T2 preparation (T2 Prep) sequence used for coronary magnetic resonance angiography (MRA). A new adiabatic refocusing T2 Prep sequence is presented in which the magnetization is tipped into the transverse plane with a hard RF pulse and refocused using a pair of adiabatic fast-passage RF pulses. The isochromats are subsequently returned to the longitudinal axis using a hard RF pulse. Numerical simulations predict an excellent suppression of artifacts originating from B1 inhomogeneity while achieving good contrast enhancement between coronary arteries and surrounding tissue. This was confirmed by an in vivo study, in which coronary MR angiograms were obtained without a T2 Prep, with an MLEV weighted T2 Prep and the proposed adiabatic T2 Prep. Improved quantitative and qualitative coronary MRA image measurement was achieved using the adiabatic T2 Prep at 3 T.
Mots-clé
Adult, Artifacts, Coronary Vessels/anatomy & histology, Female, Heart/anatomy & histology, Humans, Image Processing, Computer-Assisted, Imaging, Three-Dimensional, Magnetic Resonance Angiography/methods, Male, Statistics, Nonparametric
Pubmed
Web of science
Open Access
Oui
Création de la notice
02/03/2010 16:04
Dernière modification de la notice
20/08/2019 14:38