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Quantitative diffusion coefficient maps using fast spin-echo MRI

Brockstedt, Sara LU ; Thomsen, C; Wirestam, Ronnie LU ; Holtås, Stig LU and Ståhlberg, Freddy LU (1998) In Magnetic Resonance Imaging 16(8). p.877-886
Abstract
In this work, we have evaluated the performance of a diffusion-sensitive fast spin-echo (FSE) pulse sequence. The proposed pulse sequence utilises velocity-compensating diffusion-encoding gradients and includes the collection of navigator echoes. Spoiler gradients were inserted in the slice-selecting direction to minimise effects from stimulated echoes. Calculations of the b values showed that cross-terms between imaging gradients and diffusion gradients only led to a marginal increase of b values. Pixel-wise calculation of apparent diffusion coefficient (ADC) maps was performed numerically, considering cross-terms between diffusion-encoding and imaging gradients. The sequences investigated used echo train lengths of 16, 8 and 4 echoes and... (More)
In this work, we have evaluated the performance of a diffusion-sensitive fast spin-echo (FSE) pulse sequence. The proposed pulse sequence utilises velocity-compensating diffusion-encoding gradients and includes the collection of navigator echoes. Spoiler gradients were inserted in the slice-selecting direction to minimise effects from stimulated echoes. Calculations of the b values showed that cross-terms between imaging gradients and diffusion gradients only led to a marginal increase of b values. Pixel-wise calculation of apparent diffusion coefficient (ADC) maps was performed numerically, considering cross-terms between diffusion-encoding and imaging gradients. The sequences investigated used echo train lengths of 16, 8 and 4 echoes and were encoded in either the slice-, frequency- or phase-encoding direction. In order to allow for higher b values a pulse-sequence version using non-motion compensating diffusion-encoding gradients was written. Phantom measurements were performed and the diffusion coefficients of water and acetone were reasonable. Seven healthy volunteers (age 28-50 years) were examined and apparent diffusion coefficient values agreed well with expected values. Diffusion-weighted images, apparent diffusion coefficient maps and images corresponding to the trace of the diffusion tensor of good quality were retrieved in vivo. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Navigator echoes Article Outline, Phase correction, Motion-compensating gradients, Diffusion, Fast spin-echo
in
Magnetic Resonance Imaging
volume
16
issue
8
pages
877 - 886
publisher
Elsevier
external identifiers
  • pmid:9814769
  • scopus:0031770120
ISSN
1873-5894
DOI
10.1016/S0730-725X(98)00002-2
language
English
LU publication?
yes
id
5200f840-92a1-4728-8089-d5f19975f33b (old id 1112689)
date added to LUP
2008-07-11 09:04:38
date last changed
2017-05-21 03:29:43
@article{5200f840-92a1-4728-8089-d5f19975f33b,
  abstract     = {In this work, we have evaluated the performance of a diffusion-sensitive fast spin-echo (FSE) pulse sequence. The proposed pulse sequence utilises velocity-compensating diffusion-encoding gradients and includes the collection of navigator echoes. Spoiler gradients were inserted in the slice-selecting direction to minimise effects from stimulated echoes. Calculations of the b values showed that cross-terms between imaging gradients and diffusion gradients only led to a marginal increase of b values. Pixel-wise calculation of apparent diffusion coefficient (ADC) maps was performed numerically, considering cross-terms between diffusion-encoding and imaging gradients. The sequences investigated used echo train lengths of 16, 8 and 4 echoes and were encoded in either the slice-, frequency- or phase-encoding direction. In order to allow for higher b values a pulse-sequence version using non-motion compensating diffusion-encoding gradients was written. Phantom measurements were performed and the diffusion coefficients of water and acetone were reasonable. Seven healthy volunteers (age 28-50 years) were examined and apparent diffusion coefficient values agreed well with expected values. Diffusion-weighted images, apparent diffusion coefficient maps and images corresponding to the trace of the diffusion tensor of good quality were retrieved in vivo.},
  author       = {Brockstedt, Sara and Thomsen, C and Wirestam, Ronnie and Holtås, Stig and Ståhlberg, Freddy},
  issn         = {1873-5894},
  keyword      = {Navigator echoes
Article Outline,Phase correction,Motion-compensating gradients,Diffusion,Fast spin-echo},
  language     = {eng},
  number       = {8},
  pages        = {877--886},
  publisher    = {Elsevier},
  series       = {Magnetic Resonance Imaging},
  title        = {Quantitative diffusion coefficient maps using fast spin-echo MRI},
  url          = {http://dx.doi.org/10.1016/S0730-725X(98)00002-2},
  volume       = {16},
  year         = {1998},
}