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. Author manuscript; available in PMC: 2011 Feb 10.
Published in final edited form as: J Magn Reson Imaging. 2009 Sep;30(3):473–480. doi: 10.1002/jmri.21834

Table 3.

Median raw SNR and normalized SNR (nSNR: cm−3 min−1/2) values for all spectroscopic imaging techniques for NAA in 10 volunteers. Standard deviation between the 10 scans is shown (for nSNR only) as median ± SD. Median metabolite ratios are also shown for each technique (Cho:NAA and Cre:NAA). Voxels were considered to have aliased lipid if Lip SNR was greater than 25% of median NAA SNR in NAWM. Flyback data were not acquired on one volunteer and symmetric data were not acquired on another.

Encoding Technique NAA raw SNR NAA nSNR Cho:NAA Cre:NAA % of voxels with aliased lipid
Traditional MRSI 46.28 10.10 ± 1.09 (22.28%) 0.48 0.39 0.0 ± 5
Ellipsoidal MRSI 68.75 9.22 ± 1.07 (23.48%) 0.49 0.40 0.0 ± 7
SENSE MRSI (Rx=2) 20.54 6.16 ± 1.14 (23.19%) 0.48 0.43 16.2 ± 27
SENSE w/REG 27.05 8.11 ± 1.74 (24.49%) 0.49 0.42 12.3 ± 20
Flyback EPSI 25.87 8.29 ± 0.83 (21.12%) 0.51 0.39 2.0 ± 4
Symmetric EPSI 24.73 8.05 ± 0.76 (26.18%) 0.51 0.37 0.0 ± 2
Symmetric w/ramps 21.89 8.45 ± 1.14 (24.46%) 0.50 0.37 2.2 ± 4