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MRI thermometry in phantoms by use of the proton resonance frequency shift method: application to interstitial laser thermotherapy

Olsrud, Johan LU ; Wirestam, Ronnie LU ; Brockstedt, Sara LU ; Nilsson, Annika M K; Tranberg, Karl-Göran LU ; Ståhlberg, Freddy LU and Persson, Bertil R LU (1998) In Physics in Medicine and Biology 43(9). p.2597-2613
Abstract
In this work the temperature dependence of the proton resonance frequency was assessed in agarose gel with a high melting temperature (95 degrees C) and in porcine liver in vitro at temperatures relevant to thermotherapy (25-80 degrees C). Furthermore, an optically tissue-like agarose gel phantom was developed and evaluated for use in MRI. The phantom was used to visualize temperature distributions from a diffusing laser fibre by means of the proton resonance frequency shift method. An approximately linear relationship (0.0085 ppm degrees C(-1)) between proton resonance frequency shift and temperature change was found for agarose gel, whereas deviations from a linear relationship were observed for porcine liver. The optically tissue-like... (More)
In this work the temperature dependence of the proton resonance frequency was assessed in agarose gel with a high melting temperature (95 degrees C) and in porcine liver in vitro at temperatures relevant to thermotherapy (25-80 degrees C). Furthermore, an optically tissue-like agarose gel phantom was developed and evaluated for use in MRI. The phantom was used to visualize temperature distributions from a diffusing laser fibre by means of the proton resonance frequency shift method. An approximately linear relationship (0.0085 ppm degrees C(-1)) between proton resonance frequency shift and temperature change was found for agarose gel, whereas deviations from a linear relationship were observed for porcine liver. The optically tissue-like agarose gel allowed reliable MRI temperature monitoring, and the MR relaxation times (T1 and T2) and the optical properties were found to be independently alterable. Temperature distributions around a diffusing laser fibre, during irradiation and subsequent cooling, were assessed with high spatial resolution (voxel size = 4.3 mm3) and with random uncertainties ranging from 0.3 degrees C to 1.4 degrees C (1 SD) with a 40 s scan time. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Physics in Medicine and Biology
volume
43
issue
9
pages
2597 - 2613
publisher
IOP Publishing
external identifiers
  • pmid:9755948
  • scopus:0031716008
ISSN
1361-6560
language
English
LU publication?
yes
id
ff32db22-5698-4672-ab1d-57f8b9a536a7 (old id 1112693)
alternative location
http://www.iop.org/EJ/article/0031-9155/43/9/012/m80912.pdf
date added to LUP
2008-07-11 09:03:54
date last changed
2017-05-21 03:38:17
@article{ff32db22-5698-4672-ab1d-57f8b9a536a7,
  abstract     = {In this work the temperature dependence of the proton resonance frequency was assessed in agarose gel with a high melting temperature (95 degrees C) and in porcine liver in vitro at temperatures relevant to thermotherapy (25-80 degrees C). Furthermore, an optically tissue-like agarose gel phantom was developed and evaluated for use in MRI. The phantom was used to visualize temperature distributions from a diffusing laser fibre by means of the proton resonance frequency shift method. An approximately linear relationship (0.0085 ppm degrees C(-1)) between proton resonance frequency shift and temperature change was found for agarose gel, whereas deviations from a linear relationship were observed for porcine liver. The optically tissue-like agarose gel allowed reliable MRI temperature monitoring, and the MR relaxation times (T1 and T2) and the optical properties were found to be independently alterable. Temperature distributions around a diffusing laser fibre, during irradiation and subsequent cooling, were assessed with high spatial resolution (voxel size = 4.3 mm3) and with random uncertainties ranging from 0.3 degrees C to 1.4 degrees C (1 SD) with a 40 s scan time.},
  author       = {Olsrud, Johan and Wirestam, Ronnie and Brockstedt, Sara and Nilsson, Annika M K and Tranberg, Karl-Göran and Ståhlberg, Freddy and Persson, Bertil R},
  issn         = {1361-6560},
  language     = {eng},
  number       = {9},
  pages        = {2597--2613},
  publisher    = {IOP Publishing},
  series       = {Physics in Medicine and Biology},
  title        = {MRI thermometry in phantoms by use of the proton resonance frequency shift method: application to interstitial laser thermotherapy},
  volume       = {43},
  year         = {1998},
}