Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy
- High Field Magnetic Resonance Imaging and Spectroscopy
Research Area: musculoskeletal MR; neuroimaging; metabolic MR imaging and spectroscopy
- Pulse Sequences and Image Reconstruction
- Skeletal muscle MRS and MRI
I am a biomedical engineer by training and focused during my master thesis and my PhD studies mainly on pulse sequence development on Siemens MR scanners using IDEA. The fact that a simultaneous acquisition of proton and X-nuclei signals was theoretically feasible, but technically challenging (requires hardware/software modification) and had not been implemented at ultra-high field (7 tesla), motivated me and became the main focus of my PhD thesis. This principle of interleaved multi-nuclear data acquisition was then applied to combine two individual pulse sequences (1H Arterial Spin Labelling MRI and 31P semi-laser MR spectroscopy), which allows for a simultaneous assessment of dynamic perfusion, T2*-weighted and metabolic data. The development and application of the method resulted in three individual first author manuscripts (MRM 2017 and 2020, NMR in Biomed 2018), which were investigating inhomogeneities of the metabolic and functional response to exercise across the healthy human calf and along single muscle groups. Recently I implemented a double quantum filter 1H MR spectroscopy sequence for application on both 3T and 7T Siemens systems, which was tested as proof of concept on a phantom containing a lactate solution.
Techniques, methods & infrastructure
Pulse sequence development (Siemens IDEA) and data processing for MR spectroscopy and imaging at high field (3 T) and ultra high field (7 T) (dynamic 31 P spectroscopy, time resolved 1 H perfusion imaging, multi-nuclear interleaved NMR)
Intracellular high energy metabolism and oxygenation of healthy human muscle tissue (functional, hemodynamic and metabolic response to voluntary exercise and/or ischemia)
Resting and post exercise lactate quantification in healthy human muscles (Double Quantum Filtered 1 H MR spectroscopy)
- Niess F, Schmid AI, Bogner W, Wolzt M, Carlier P, Trattnig S, Moser E, Meyerspeer M. Interleaved 31P MRS/1H ASL for analysis of metabolic and functional heterogeneity along human lower leg muscles at 7T. Magnetic Resonance in Medicine 2020, 83(6), pp.1909, Available at: http://dx.doi.org/10.1002/mrm.2808.
- Niess F, Fiedler GB, Schmid AI, Laistler E, Frass-Kriegl R, Wolzt M, Moser E, Meyerspeer M. Dynamic multivoxel-localized 31P MRS during plantar flexion exercise with variable knee angle. NMR in Biomedicine 2018, 31(6), p.e3905. Available at: http://dx.doi.org/10.1002/nbm.3905.
- Niess F, Fiedler GB, Schmid AI, Goluch S, Kriegl R, Wolzt M, Moser E, Meyerspeer M. Interleaved multivoxel 31P MR spectroscopy. Magnetic Resonance in Medicine 2017, 77(3), pp.921, Available at: http://dx.doi.org/10.1002/mrm.2617.
- Fiedler G.B, Schmid AI, Goluch S, Schewzow K, Laistler E, Niess F, Unger E, Wolzt M, Mirzahosseini A, Kemp GJ, Moser E, Meyerspeer M. Skeletal muscle ATP synthesis and cellular H+ handling measured by localized 31P-MRS during exercise and recovery. Scientific Reports 2016, 6(1). Available at: http://dx.doi.org/10.1038/srep32037.
- Fiedler G.B & Meyerspeer M, Schmid AI, Goluch S, Schewzow K, Laistler E, Mirzahosseini A, Niess F, Unger E, Wolzt M, Moser E. Localized semi-LASER dynamic 31P magnetic resonance spectroscopy of the soleus during and following exercise at 7T. Magnetic Resonance Materials in Physics, Biology and Medicine 2015, Available at: http://dx.doi.org/10.1007/s10334-015-0484-.