Locally focused 3D coronary imaging using volume-selective RF excitation
This paper describes a locally focused magnetic resonance (MR) imaging method for three‐dimensional (3D) zonal echoplanar coronary angiography using volume‐selective radiofrequency (RF) excitation. Spatially variable resolution was used for delineating coronary arteries and reducing the effect of re...
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Published in | Magnetic resonance in medicine Vol. 41; no. 1; pp. 171 - 178 |
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Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
New York
John Wiley & Sons, Inc
01.01.1999
Williams & Wilkins |
Subjects | |
Online Access | Get full text |
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Summary: | This paper describes a locally focused magnetic resonance (MR) imaging method for three‐dimensional (3D) zonal echoplanar coronary angiography using volume‐selective radiofrequency (RF) excitation. Spatially variable resolution was used for delineating coronary arteries and reducing the effect of residual signals caused by the imperfect excitation profile of the RF pulse. The use of variable resolution enabled the derivation of basis functions having different spatial characteristics pertaining to regional object details, and a significantly smaller number of phase‐encoded signal measurements was needed for image reconstruction. Based on the relative significance of each required phase‐encoding step, real‐time phase‐encode reordering was used to minimize the effect of respiratory motion during coronary imaging. To eliminate Nyquist ghosting in oblique echoplanar imaging, the echoplanar data acquired during forward and reverse echoes were reconstructed separately and then averaged with spatial registration for improving the signal‐to‐noise ratio. The technique was evaluated with phantom experiments and right coronary artery images of 11 asymptomatic volunteers using a 0.5 T MR system. A marked improvement in image quality has been achieved despite a 30% reduction in imaging time. Magn Reson Med 41:171‐178. © 1999 Wiley‐Liss, Inc. |
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Bibliography: | istex:858747E27F4DC3A6DE585F319DE3181979FDD882 CORDA-the heart charity Wellcome Trust ArticleID:MRM24 ark:/67375/WNG-27QWSGT5-F ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0740-3194 1522-2594 |
DOI: | 10.1002/(SICI)1522-2594(199901)41:1<171::AID-MRM24>3.0.CO;2-5 |