Identification of signal bias in the variable flip angle method by linear display of the algebraic Ernst equation
Helms, Gunther LU
; Dathe, Henning
; Weiskopf, Nikolaus
and Dechent, Peter
(2011)
In Magnetic Resonance in Medicine
66(3).
p.669-677
- Abstract
- A novel linear parameterization for the variable flip angle
method for longitudinal relaxation time T1 quantification from
spoiled steady state MRI is derived from the half angle tangent
transform, t, of the flip angle. Plotting the signal S at coordinates
x=St and y=S/t, respectively, establishes a line that
renders signal amplitude and relaxation term separately as y-intercept
and slope. This representation allows for estimation of
the respective parameter from the experimental data. A comprehensive
analysis of noise propagation is performed. Numerical
results for efficient optimization of longitudinal relaxation
time and proton density mapping... (More) - A novel linear parameterization for the variable flip angle
method for longitudinal relaxation time T1 quantification from
spoiled steady state MRI is derived from the half angle tangent
transform, t, of the flip angle. Plotting the signal S at coordinates
x=St and y=S/t, respectively, establishes a line that
renders signal amplitude and relaxation term separately as y-intercept
and slope. This representation allows for estimation of
the respective parameter from the experimental data. A comprehensive
analysis of noise propagation is performed. Numerical
results for efficient optimization of longitudinal relaxation
time and proton density mapping experiments are derived.
Appropriate scaling allows for a linear presentation of data that
are acquired at different short pulse repetition times, TR << T1
thus increasing flexibility in the data acquisition by removing the
limitation of a single pulse repetition time. Signal bias, like due
to slice-selective excitation or imperfect spoiling, can be readily
identified by systematic deviations from the linear plot. The
method is illustrated and validated by 3T experiments on phantoms
and human brain. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/8773491
- author
- Helms, Gunther
LU
; Dathe, Henning
; Weiskopf, Nikolaus
and Dechent, Peter
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Magnetic Resonance in Medicine
- volume
- 66
- issue
- 3
- pages
- 669 - 677
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- scopus:80051689849
- pmid:21432900
- ISSN
- 1522-2594
- DOI
- 10.1002/mrm.22849
- project
- Algebraization of MRI signal equations
- language
- English
- LU publication?
- yes
- additional info
- 3
- id
- 56fade86-e675-4829-bd83-04464f4e0061 (old id 8773491)
- alternative location
- http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3193384/
- date added to LUP
- 2016-04-01 10:45:21
- date last changed
- 2022-02-10 05:43:27
@article{56fade86-e675-4829-bd83-04464f4e0061,
abstract = {{A novel linear parameterization for the variable flip angle<br/><br>
method for longitudinal relaxation time T1 quantification from<br/><br>
spoiled steady state MRI is derived from the half angle tangent<br/><br>
transform, t, of the flip angle. Plotting the signal S at coordinates<br/><br>
x=St and y=S/t, respectively, establishes a line that<br/><br>
renders signal amplitude and relaxation term separately as y-intercept<br/><br>
and slope. This representation allows for estimation of<br/><br>
the respective parameter from the experimental data. A comprehensive<br/><br>
analysis of noise propagation is performed. Numerical<br/><br>
results for efficient optimization of longitudinal relaxation<br/><br>
time and proton density mapping experiments are derived.<br/><br>
Appropriate scaling allows for a linear presentation of data that<br/><br>
are acquired at different short pulse repetition times, TR << T1<br/><br>
thus increasing flexibility in the data acquisition by removing the<br/><br>
limitation of a single pulse repetition time. Signal bias, like due<br/><br>
to slice-selective excitation or imperfect spoiling, can be readily<br/><br>
identified by systematic deviations from the linear plot. The<br/><br>
method is illustrated and validated by 3T experiments on phantoms<br/><br>
and human brain.}},
author = {{Helms, Gunther and Dathe, Henning and Weiskopf, Nikolaus and Dechent, Peter}},
issn = {{1522-2594}},
language = {{eng}},
number = {{3}},
pages = {{669--677}},
publisher = {{John Wiley & Sons Inc.}},
series = {{Magnetic Resonance in Medicine}},
title = {{Identification of signal bias in the variable flip angle method by linear display of the algebraic Ernst equation}},
url = {{http://dx.doi.org/10.1002/mrm.22849}},
doi = {{10.1002/mrm.22849}},
volume = {{66}},
year = {{2011}},
}