brain; lipids; magnetic resonance spectroscopy; metabolic imaging; magnetic resonance imaging; methodology; obesity; diffusion; neurotransmitters; depression; diurnal variation; microstructure; sleep; skeletal muscle
Dziadosz Martyna, Bogner Wolfgang, Kreis Roland (2020), Non‐water‐excitation MR spectroscopy techniques to explore exchanging protons in human brain at 3 T, in
Magnetic Resonance in Medicine, 84, 2352-2363.
Hoefemann Maike, Bolliger Christine Sandra, Chong Daniel G.Q., Veen Jan Willem, Kreis Roland (2020), Parameterization of metabolite and macromolecule contributions in interrelated MR spectra of human brain using multidimensional modeling, in
{NMR} in Biomedicine, 33(9), e4328.
Near Jamie, Harris Ashley D., Juchem Christoph, Kreis Roland, Marjańska Małgorzata, Öz Gülin, Slotboom Johannes, Wilson Martin, Gasparovic Charles (2020), Preprocessing, analysis and quantification in single‐voxel magnetic resonance spectroscopy: experts' consensus recommendations, in
{NMR} in Biomedicine, e4257.
Krššák Martin, Lindeboom Lucas, Schrauwen-Hinderling Vera, Szczepaniak Lidia S., Derave Wim, Lundbom Jesper, Befroy Douglas, Schick Fritz, Machann Jürgen, Kreis Roland, Boesch Chris (2020), Proton magnetic resonance spectroscopy in skeletal muscle: Experts' consensus recommendations, in
{NMR} in Biomedicine, e4266.
Kreis Roland, Boer Vincent, Choi In-Young, Cudalbu Cristina, Graaf Robin A., Gasparovic Charles, Heerschap Arend, Krššák Martin, Lanz Bernard, Maudsley Andrew A., Meyerspeer Martin, Near Jamie, Öz Gülin, Posse Stefan, Slotboom Johannes, Terpstra Melissa, Tkáč Ivan, Wilson Martin, Bogner Wolfgang (2020), Terminology and concepts for the characterization of in vivo MR spectroscopy methods and MR spectra: Background and experts' consensus recommendations, in
{NMR} in Biomedicine, e4347.
DöringAndré, KreisRoland (2019), Magnetic resonance spectroscopy extended by oscillating diffusion gradients: Cell-specific anomalous diffusion as a probe for tissue microstructure in human brain., in
Neuroimage, 202, 116075.
Hoefemann Maike, Adalid Victor, Kreis Roland (2019), Optimizing acquisition and fitting conditions for 1 H MR spectroscopy investigations in global brain pathology, in
{NMR} in Biomedicine, 32(11), e4161.
SP Kyathanahally, A Döring, R Kreis (2018), Deep learning approaches for detection and removal of ghosting artifacts in MR spectroscopy., in
Magnetic resonance in medicine, 80, 851-863.
A Döring, V Adalid, C Boesch, R Kreis (2018), Diffusion-weighted magnetic resonance spectroscopy boosted by simultaneously acquired water reference signals., in
Magnetic resonance in medicine, 80(6), 2326-2338.
BackgroundMagnetic resonance imaging (MRI) and spectroscopy (MRS) provide non-invasive modalities to explore human morphology, function and metabolism. MRS is widespread as biomedical research tool to investigate chemical fingerprints of human physiology in health and disease. Clinical applications still lag behind for lack of a simple push-button tool and limited robustness. In research on the other hand, applications abound while progress is far from complete. It relies on dedicated explorations using the latest technological advances in MR hardware and methodology, but also on specific step-by-step optimization of existing methods under the aspect of specific metabolic imaging targets. Ultra-high magnetic fields (UHF, 7-9.4T) provide the arena to overcome previous limitations in signal-to-noise, while ultra-strong gradient (USG) systems are now available to obliterate previous limits in diffusion-related techniques. In addition, techniques like exchange saturation transfer (CEST) MRI and relaxation enhancement MRS extend the range of metabolites of high clinical interest, while using an interplay of optimized acquisition and processing algorithms promises pushing into the micromolar range. The novel methods will immediately be applied to address diverse crucial open issues in human physiology: 1) Neurotransmitter levels, like GABA, glutamate come into focus for non-invasive mapping by MR in humans. 2) Accumulation of ectopic lipids in diabetes and obesity, where it is of prime interest to distinguish between beneficial and detrimental lipid accrual. 3) Physiology of sleep and diurnal homeostasis, where invasive animal data suggests a major role for sleep in detoxification and initial cardiac studies show changes in ectopic lipd levels.Working HypothesesA) “Use of forefront technology and methods” and B) “Optimization of all steps in state-of-the-art methodology” are two paths that lead in this project to substantial lowering of the detection thresholds for metabolite levels in humans.C) Seminal findings with wide-ranging consequences will emerge from application of the developed techniques for distinct applications in the context of neurophysiology and ectopic lipids. Methods & Expected ResultsForefront technology and a collaboration network at five prime MR research sites allow the use and combination of pioneering UHF and USG systems with sophisticated acquisition and processing methods, as well as a unique constellation of know-how, including field probes and optical devices for measurement stabilization, non-water-suppressed sequences for signal enhancement, as well as specialized expertise on MR technology, spectral fitting, as well as sleep physiology, ectopic lipids and serotonin disorders.Expected Value of the Proposed ProjectThe proposal aims at extending methodology towards more sensitive and robust MRS and metabolic imaging on one side and at novel uses in physiology and medicine on the other. The use of forefront methodology will pave the way for further technical innovation, but also provides results that can be used on clinical systems. The specific applications promise to provide groundbreaking new findings themselves. In particular, any means to further characterize diurnal homeostasis and sleep physiology may have substantial impact in neurodegeneration research. In addition,lipid droplet size may become a crucial parameter to judge the interplay of ectopic fat deposition, insulin resistance and benefits from exercise training and specific diets.