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)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1112689
- author
- Brockstedt, Sara
LU
; Thomsen, C
; Wirestam, Ronnie
LU
; Holtås, Stig
LU
and Ståhlberg, Freddy
LU
- organization
- publishing date
- 1998
- 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
- 2016-04-01 11:39:38
- date last changed
- 2022-01-26 08:22:23
@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}},
keywords = {{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}},
doi = {{10.1016/S0730-725X(98)00002-2}},
volume = {{16}},
year = {{1998}},
}