Wiley, Magnetic Resonance in Medicine, 3(68), p. 662-670, 2011
DOI: 10.1002/mrm.23288
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Proton MR spectroscopic imaging of the human brain at ultra high field (≥7T) is challenging due to increased RF power deposition, increased magnetic field B0 inhomogeneity and increased RF magnetic field inhomogeneity. And, especially for multi-slice sequences, these effects directly inhibit the potential gains of higher magnetic field and can even cause a reduction in data quality. However, recent developments in dynamic B0 magnetic field shimming and dynamic multi-transmit RF control allow for new acquisition strategies. Therefore, in this work slice-by-slice B0 and B1 shimming was developed to optimize both B0 magnetic field homogeneity and nutation angle over a large portion of the brain. Together with a low-power water and lipid suppression sequence and pulse-acquire spectroscopic imaging, a multi-slice MRSI sequence is shown to be feasible at 7T. This now allows for multi-slice metabolic imaging of the human brain with high sensitivity and high chemical shift resolution at ultra high field.