Linked Life Data

10642732

Source:http://linkedlifedata.com/resource/pubmed/id/10642732

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-3-14
pubmed:abstractText
The proton-resonance frequency (PRF) shift method of MR thermometry provides an easy and practical means of quantitatively monitoring in vivo temperatures for MR image-guided thermal-coagulation therapy. However, reported discrepancies in the numerical value of the PRF-thermal coefficient persist, when measured in a variety of experimental conditions and in different tissue types, both ex vivo and in vivo. In this report, a potential source of variation in the PRF-shift method of thermometry is identified that manifests as a constant incremental phase shift per unit change in temperature that is independent of the echo-time setting, when constructing temperature-sensitive phase images from a gradient-echo pulse sequence. It is proposed that this confounding phase-shift offset arises from thermally induced changes in the electrical conductivity of the material. To this end, it is demonstrated that the MR-derived temperature changes could be in error by as much as 28%, as measured from a simple calibration experiment on freshly excised cow liver. A simple method of overcoming this phase-shift offset is described.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0740-3194
pubmed:author
pubmed:issnType
Print
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
62-71
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Proton-resonance frequency shift MR thermometry is affected by changes in the electrical conductivity of tissue.
pubmed:affiliation
Department of Medical Biophysics, University of Toronto, Sunnybrook and Women's College Health Science Center, Ontario, Canada. peters@sten.sunnybrook.utoronto.ca
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't