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Abstract #1731

Signal Scaling Improves the Performance of Single-Voxel MR Spectroscopy Based on Segmented 2D-Selective RF Excitations

Jrgen Finsterbusch1, 2

1Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; 2Neuroimage Nord, University Medical Centers Hamburg-Kiel-Lbeck, Hamburg-Kiel-Lbeck, Germany

2D-selective RF excitations are a promising tool to minimize partial volume effects in single-voxel MRS. Segmentation is often applied to avoid excessive 2DRF pulse lengths. But for some trajectories like the blipped-planar trajectory, segmentation reduces the signal efficiency because many segments cover only outer k-space lines and yield low flip angles and signal amplitudes. Here, it is shown that the signal-to-noise ratio can be increased significantly by applying all segments with the full flip angle and scaling down the acquired signal accordingly. This does not alter the signal amplitude but can reduce the noise level considerably as is demonstrated experimentally.

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Keywords

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