B1-insensitive T2 preparation for improved coronary magnetic resonance angiography at 3 T.
Details
Serval ID
serval:BIB_7CEAEE6CBFF9
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
B1-insensitive T2 preparation for improved coronary magnetic resonance angiography at 3 T.
Journal
Magnetic Resonance In Medicine
ISSN
0740-3194[print], 0740-3194[linking]
Publication state
Published
Issued date
2006
Volume
55
Number
4
Pages
858-864
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Publication Status: ppublish
Abstract
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.
Keywords
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
Yes
Create date
02/03/2010 17:04
Last modification date
20/08/2019 15:38