% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@PHDTHESIS{Shymanskaya:787158,
author = {Shymanskaya, Aliaksandra},
othercontributors = {Shah, Nadim Joni and Stahl, Achim and Nagel, Armin},
title = {{D}evelopment and implementation of novel experimental
methods for the quantification of the healthy and diseased
brain by means of sodium magnetic resonance imaging},
school = {RWTH Aachen University},
type = {Dissertation},
address = {Aachen},
reportid = {RWTH-2020-03946},
pages = {1 Online-Ressource (155 Seiten) : Illustrationen,
Diagramme},
year = {2020},
note = {Veröffentlicht auf dem Publikationsserver der RWTH Aachen
University; Dissertation, RWTH Aachen University, 2020},
abstract = {Sodium magnetic resonance imaging (MRI) is used to
investigate metabolic processes in tissues. Sodium plays a
role in the maintenance of cell milieu and volume, as well
as in signal transmittance. Its concentration in
intracellular and extracellular space is closely regulated
in healthy tissue, and, therefore, any deviations in sodium
distribution are a sign of disease. Due to the quadrupolar
nature of its nucleus, sodium can relax biexponentially.
Multiple quantum coherences (MQCs) can evolve if the two
relaxation constants differ. This represents the difference
between sodium in fluid, which does not develop significant
multiple quantum coherences, and so-called “restricted”
sodium. In this thesis, a method is suggested for estimating
tissue sodium parameters using models for healthy and
diseased tissue. A quantification routine was created, which
estimates several tissue parameters, such as tissue sodium
concentration, intracellular sodium concentration, and
intracellular molar and volume fractions. For this, an
enhanced SISTINA sequence with two relaxation-weighted
read-outs, to deliver three different contrasts, was
developed. This approach enables the estimation of several
parameters from one measurement. The data evaluation routine
proposed in this thesis involves the use of simulations to
estimate the precision of several fitting approaches. An
appropriate, efficient method was applied in healthy
subjects to create a reference. Finally, cerebral glioma and
multiple sclerosis patients were measured and sodium tissue
parameters were estimated. In cerebral gliomas, a positive
correlation between sodium parameters and isocitrate
dehydrogenase (IDH) mutational status was discovered.},
cin = {134005 / 130000 / 535000-5},
ddc = {530},
cid = {$I:(DE-82)134005_20180710$ / $I:(DE-82)130000_20140620$ /
$I:(DE-82)535000-5_20140620$},
typ = {PUB:(DE-HGF)11},
doi = {10.18154/RWTH-2020-03946},
url = {https://publications.rwth-aachen.de/record/787158},
}
guest ::