The temporal and spatial resolution of an MR experiment is always influenced by the available signal-to-noise ratio (SNR). In general, SNR increases with a higher static magnetic field (B0). Magnetic resonance spectroscopic imaging may benefit from the ultra-high field, however novel approaches are necessary to overcome the technical challenges that arise at such high magnetic field strengths. In this talk we focus on the specifics of UHF MRSI and present the most recent MRSI methods where the SNR gain can be traded off for higher spatial or temporal resolution.
· Understanding of the major advantages and drawbacks of MRSI methods at ultra-high fields
· Get an overview of the most recent MRSI methods
· Explore a world beyond vendor-provided MRSI sequences
Introduction
Magnetic resonance spectroscopic imaging (MRSI) is a non-invasive technique that merges the principles of magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI). It provides valuable insights into biochemical processes inside the human (or animal) body. The temporal (i.e. speed) and spatial resolution of an MR experiment is always influenced by the available signal-to-noise ratio (SNR). These three factors are closely linked together. Every MRSI experiment is a tradeoff between them in order to achieve short measurement times, high spatial resolution and sufficient SNR for quantification. In general, SNR increases with a higher static magnetic field (B0) 1. In addition, larger chemical shift dispersion and a reduction in J-coupling of strongly coupled systems is observed at UHF 2. Therefore, a recent trend towards installation of ultra-high field (UHF, i.e. B0 ≥7T) MR systems may be beneficial for MRSI. However, novel approaches are necessary to overcome the technical challenges that arise at such a high magnetic field strength 3.1. Trattnig, S. et al. Clinical applications at ultrahigh field (7 T). Where does it make the difference? NMR Biomed. 29, 1316–1334 (2016).
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