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Accuracy of q-space related parameters in MRI: Simulations and phantom measurements

Lätt, Jimmy LU ; Nilsson, Markus LU ; Malmborg, Carin LU ; Rosquist, Hannah; Wirestam, Ronnie LU ; Ståhlberg, Freddy LU ; Topgaard, Daniel LU and Brockstedt, Sara LU (2007) In IEEE Transactions on Medical Imaging 26(11). p.1437-1447
Abstract
The accuracy of q-space measurements was evaluated at a 3.0-T clinical magnetic resonance imaging (MRI) scanner, as compared with a 4.7-T nuclear magnetic resonance (NMR) spectrometer. Measurements were performed using a stimulated-echo pulse-sequence on n-decane as well as on polyethylene glycol (PEG) mixed with different concentrations of water, in order to obtain bi-exponential signal decay curves. The diffusion coefficients as well as the modelled diffusional kurtosis K-fit, were obtained from the signal decay curve, while the full-width at half-maximum (FWHM) and the diffusional kurtosis K were obtained from the displacement distribution. Simulations of restricted diffusion, under conditions similar to those obtainable with a clinical... (More)
The accuracy of q-space measurements was evaluated at a 3.0-T clinical magnetic resonance imaging (MRI) scanner, as compared with a 4.7-T nuclear magnetic resonance (NMR) spectrometer. Measurements were performed using a stimulated-echo pulse-sequence on n-decane as well as on polyethylene glycol (PEG) mixed with different concentrations of water, in order to obtain bi-exponential signal decay curves. The diffusion coefficients as well as the modelled diffusional kurtosis K-fit, were obtained from the signal decay curve, while the full-width at half-maximum (FWHM) and the diffusional kurtosis K were obtained from the displacement distribution. Simulations of restricted diffusion, under conditions similar to those obtainable with a clinical MRI scanner, were carried out assuming various degrees of violation of the short gradient pulse (SGP) condition and of the long diffusion time limit., The results indicated that an MRI system can not be used for quantification of structural sizes less than about 10 mu m by means of FWHM since the parameter underestimates the confinements due to violation of the SGP condition. However, FWHM can still be used as an important contrast parameter. The obtained kurtosis values were lower than expected from theory and the results showed that care must be taken when interpreting a kurtosis estimate deviating from zero. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
q-space, kurtosis magnetic resonance, displacement distribution, diffusion, imaging (MRI)
in
IEEE Transactions on Medical Imaging
volume
26
issue
11
pages
1437 - 1447
publisher
IEEE--Institute of Electrical and Electronics Engineers Inc.
external identifiers
  • wos:000250897700003
  • scopus:35648949433
ISSN
1558-254X
DOI
10.1109/TMI.2007.907278
language
English
LU publication?
yes
id
29e5a409-acff-4d22-a033-8f863a3fafd7 (old id 971925)
date added to LUP
2008-01-29 15:11:56
date last changed
2017-10-29 03:40:52
@article{29e5a409-acff-4d22-a033-8f863a3fafd7,
  abstract     = {The accuracy of q-space measurements was evaluated at a 3.0-T clinical magnetic resonance imaging (MRI) scanner, as compared with a 4.7-T nuclear magnetic resonance (NMR) spectrometer. Measurements were performed using a stimulated-echo pulse-sequence on n-decane as well as on polyethylene glycol (PEG) mixed with different concentrations of water, in order to obtain bi-exponential signal decay curves. The diffusion coefficients as well as the modelled diffusional kurtosis K-fit, were obtained from the signal decay curve, while the full-width at half-maximum (FWHM) and the diffusional kurtosis K were obtained from the displacement distribution. Simulations of restricted diffusion, under conditions similar to those obtainable with a clinical MRI scanner, were carried out assuming various degrees of violation of the short gradient pulse (SGP) condition and of the long diffusion time limit., The results indicated that an MRI system can not be used for quantification of structural sizes less than about 10 mu m by means of FWHM since the parameter underestimates the confinements due to violation of the SGP condition. However, FWHM can still be used as an important contrast parameter. The obtained kurtosis values were lower than expected from theory and the results showed that care must be taken when interpreting a kurtosis estimate deviating from zero.},
  author       = {Lätt, Jimmy and Nilsson, Markus and Malmborg, Carin and Rosquist, Hannah and Wirestam, Ronnie and Ståhlberg, Freddy and Topgaard, Daniel and Brockstedt, Sara},
  issn         = {1558-254X},
  keyword      = {q-space,kurtosis magnetic resonance,displacement distribution,diffusion,imaging (MRI)},
  language     = {eng},
  number       = {11},
  pages        = {1437--1447},
  publisher    = {IEEE--Institute of Electrical and Electronics Engineers Inc.},
  series       = {IEEE Transactions on Medical Imaging},
  title        = {Accuracy of q-space related parameters in MRI: Simulations and phantom measurements},
  url          = {http://dx.doi.org/10.1109/TMI.2007.907278},
  volume       = {26},
  year         = {2007},
}