Maarten J. Versluis1,2, Hermien E. Kan1,2, Wouter M. Teeuwisse1,2, Andrew G. Webb1,2
1Radiology, Leiden University Medical Center, Leiden, Netherlands; 2C.J. Gorter Center for high field MRI, Leiden University Medical Center, Leiden, Netherlands
Large variations of tip angle within a slice can lead to suboptimal pulse power optimization using standard techniques which measure the average tip angle over a slice: this effect is especially pronounced at fields of 7 T and above. Here, we show a technique which performs a volume selective power optimization in less than 5 seconds, and automatically calibrates the pulses for subsequent spectroscopy scans. Using this technique, STEAM spectra were acquired in the brain and calf muscle, in each cases resulting in spectra showing a 20-45% increase in SNR compared to calibrating for the average tip angle over a slice.
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