Esin Ozturk-Isik1, Janine M. Lupo1, Sarah J. Nelson1,2, Doug Kelley3
1Radiology and Biomedical Imaging, UCSF, San Francisco, CA, USA; 2UCSF/UCB Joint Graduate Group in Bioengineering, San Francisco, CA, USA; 3GE Healthcare, San Francisco, CA, USA
This study aims at implementing a method to reduce the B1 inhomogeneity effects in 3D PRESS MRSI at 7T. Two GRE images with flip angles of 20 and 40 were acquired and the double angle method was used to estimate the B1 field factors. The transmit gain for the PRESS MRSI was optimized using the transmit gain and the flip angle of the GRE sequence and the measured B1 field factors. This method resulted in a more uniform flip angle distribution, improved spectral peak definition and lower lipid contamination across the PRESS box volume.
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