| Susceptibility mapping in the human brain using threshold-based k-space division. | |
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MedLine Citation:
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PMID: 20432300 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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A method for calculating quantitative three-dimensional susceptibility maps from field measurements acquired using gradient echo imaging at high field is presented. This method is based on division of the three-dimensional Fourier transforms of high-pass-filtered field maps by a simple function that is the Fourier transform of the convolution kernel linking field and susceptibility, and uses k-space masking to avoid noise enhancement in regions where this function is small. Simulations were used to show that the method can be applied to data acquired from objects that are oriented at one angle or multiple angles with respect to the applied field and that the use of multiple orientations improves the quality of the calculated susceptibility maps. As part of this work, we developed an improved approach for high-pass filtering of field maps, based on using an arrangement of dipoles to model the fields generated by external structures. This approach was tested on simulated field maps from the substantia nigra and red nuclei. Susceptibility mapping was successfully applied to experimental measurements on a structured phantom and then used to make measurements of the susceptibility of the red nuclei and substantia nigra in healthy subjects at 3 and 7 T. |
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Authors:
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Sam Wharton; Andreas Schäfer; Richard Bowtell |
Publication Detail:
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Type: Journal Article |
Journal Detail:
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Title: Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine Volume: 63 ISSN: 1522-2594 ISO Abbreviation: Magn Reson Med Publication Date: 2010 May |
Date Detail:
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Created Date: 2010-04-30 Completed Date: 2010-08-05 Revised Date: - |
Medline Journal Info:
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Nlm Unique ID: 8505245 Medline TA: Magn Reson Med Country: United States |
Other Details:
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Languages: eng Pagination: 1292-304 Citation Subset: IM |
Copyright Information:
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(c) 2010 Wiley-Liss, Inc. |
Affiliation:
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Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK. |
Export Citation:
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| MeSH Terms | |
Descriptor/Qualifier:
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Algorithms* Brain / anatomy & histology* Humans Image Enhancement / methods* Image Interpretation, Computer-Assisted / methods* Imaging, Three-Dimensional / methods* Magnetic Resonance Imaging / instrumentation, methods* Phantoms, Imaging Reproducibility of Results Sensitivity and Specificity |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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