Johanna Dorst
Main Focus
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Optimize proton (1H) metabolite-cycled (MC) single-voxel localization sequence and develop a robust protocol for time-resolved magnetic resonance spectroscopy in the human brain exploiting the advantages of ultra-high field (UHF, ≥ 7T) strength.
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Develop, implement, optimize and evaluate phosphorus (31P) single-voxel localization sequences and data processing pipelines at UHF.
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Establish a basis for 31P time-resolved spectroscopy at UHF with a high spatiotemporal and spectral resolution.
Magnetic resonance spectroscopy (MRS) is a technique that
allows for the non-invasive investigation of neurochemical processes of the
human brain. The acquisition of reliable MRS data with a high spatiotemporal and
spectral resolution is paramount for answering many neuroscientific or clinical
questions. UHF offers higher signal-to-noise ratios and spectral resolution than lower fields,
which are specifically valuable for dynamic experiments, such as in functional
MRS (fMRS). Therefore, the objective of this thesis was to develop locally
specific acquisition sequences overcoming the challenges but exploiting the
advantages of UHF to acquire highly reproducible spectra with a high temporal
resolution suitable for 1H and 31P fMRS experiments in the human brain at a
field strength of 9.4T. Additionally, an efficient stimulation protocol and
robust preprocessing and quantification pipelines needed to be established.
Results demonstrate the potential of the MC technique to simultaneously detect the water BOLD effect and concentration changes of several metabolites upon neural activation. Complementary to 1H, 31P MRS provides valuable information about energy metabolism and pH. The methods developed for 31P MRS form the basis for 31P fMRS at 9.4T, which can now easily be performed in a next step.
Curriculum Vitae
Education:
Max-Planck-Institut für biologische Kybernetik, Tübingen
January 2017 - Present
PhD Student
MR Spectroscopy and Ultra-High Field Methodology
Ernst-Moritz-Arndt Universität, Greifswald
October 2014 - October 2016
M.Sc. in Physics
Master's thesis at the Swiss Federal Laboratories for Materials Science and Technology (Empa, St. Gallen) and Leibniz Institute for Plasma Science and Technology (INP Greifswald)
Ernst-Moritz-Arndt Universität, Greifswald
October 2011 - September 2014
B.Sc. in Physics
Bachelor's thesis at the Leibniz Institute for Plasma Science and Technology (INP Greifswald)