Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2010-2-17
pubmed:abstractText
Recent work has shown a dramatic contrast between GM and WM in gradient echo phase images at high field (7 T). Although this contrast is key to the exploitation of phase in imaging normal and pathological tissue, its origin remains contentious. Several sources for this contrast have been considered including iron content, myelin, deoxy-hemoglobin, or water-macromolecule interactions. Here we quantify the contribution of intravascular dHb to the GM/WM contrast in the human brain at 7 T by modulating the susceptibility of the blood using a paramagnetic contrast agent. By carrying out high resolution, dynamic, gradient echo imaging before, during and after the injection of the contrast agent, we were able to follow the change in GM/WM phase contrast and to monitor simultaneously the susceptibility of the blood. Using these data in conjunction with the known susceptibility of venous blood we estimate the upper bound for the relative contribution of dHb in the vasculature to the measured GM/WM phase contrast to be 0.48 Hz for GM close to the pial surface, and 0.27 Hz for deeper GM. These values are up to 20% of the GM/WM phase difference observed in the human brain at 7 T. Furthermore, we found that the fractional blood volume differences required to account for the observed GM/WM phase contrast are 1.3% and 0.7% for GM close to the pial surface and for deeper GM, respectively.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
1095-9572
pubmed:author
pubmed:copyrightInfo
Copyright 2009 Elsevier Inc. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
491-8
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Investigating the effect of blood susceptibility on phase contrast in the human brain.
pubmed:affiliation
Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, UK. N.Petridou@umcutrecht.nl
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't