| Composite RF pulses for B1+-insensitive volume excitation at 7 Tesla. | |
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MedLine Citation:
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PMID: 20451430 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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A new class of composite RF pulses that perform well in the presence of specific ranges of B0 and B1+ inhomogeneities has been designed for volume (non-selective) excitation in MRI. The pulses consist of numerous (approximately 100) short (approximately 10 micros) block-shaped sub-pulses each with different phases and amplitudes derived from numerical optimization. Optimized pulses are designed to be effective over a specific range of frequency offsets and transmit field variations and are thus implementable regardless of field strength, transmit coil configuration, or the subject-specific spatial distribution of the static and RF fields. In the context of 7 T human brain imaging, both simulations and phantom experiments indicate that optimized pulses result in similar on-resonance flip-angle uniformity as BIR-4 pulses but with the advantages of superior off-resonance stability and significantly reduced average power. The pulse design techniques presented here are thus well-suited for practical application in ultra-high field human MRI. |
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Authors:
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Jay Moore; Marcin Jankiewicz; Huairen Zeng; Adam W Anderson; John C Gore |
Publication Detail:
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Type: Journal Article; Research Support, N.I.H., Extramural Date: 2010-04-10 |
Journal Detail:
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Title: Journal of magnetic resonance (San Diego, Calif. : 1997) Volume: 205 ISSN: 1096-0856 ISO Abbreviation: J. Magn. Reson. Publication Date: 2010 Jul |
Date Detail:
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Created Date: 2010-06-14 Completed Date: 2010-09-17 Revised Date: 2011-08-01 |
Medline Journal Info:
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Nlm Unique ID: 9707935 Medline TA: J Magn Reson Country: United States |
Other Details:
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Languages: eng Pagination: 50-62 Citation Subset: IM |
Copyright Information:
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Copyright (c) 2010 Elsevier Inc. All rights reserved. |
Affiliation:
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Institute of Imaging Science, Vanderbilt University, 1161 21st Ave. South, MCN AA-1105, Nashville, TN 37232-2310, USA. jay.moore@vanderbilt.edu |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Algorithms Brain / anatomy & histology Computer Simulation Electromagnetic Fields Humans Image Processing, Computer-Assisted Magnetic Resonance Imaging / methods* Phantoms, Imaging Radio Waves* Software |
| Grant Support | |
ID/Acronym/Agency:
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R01 EB000461-09/EB/NIBIB NIH HHS; R01EB000461/EB/NIBIB NIH HHS |
| Comments/Corrections | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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