Table 2.
Median raw SNR and normalized SNR (nSNR: cm−3 min−1/2) values for all spectroscopic imaging techniques for NAA and Lac in a phantom (N=4 scans). Standard deviation between the 4 scans is shown (for nSNR only) as median ± SD and the median variation within each scan is also presented as %CV. The Lac:NAA median ratio is displayed in the far right column.
| Encoding Technique | NAA raw SNR | NAA nSNR | Lac raw SNR | Lac nSNR | Lac:NAA |
|---|---|---|---|---|---|
| Traditional MRSI | 190.75 | 40.83 ± 1.53 (9.10%) | 43.43 | 9.30 ± 0.12 (15.20%) | 0.23 |
| Ellipsoidal MRSI | 289.92 | 38.26 ± 1.23 (9.09%) | 65.53 | 8.65 ± 0.21 (14.86%) | 0.23 |
| SENSE MRSI (Rx=2) | 83.86 | 25.15 ± 0.77 (16.64%) | 19.17 | 5.75 ± 0.23 (21.22%) | 0.23 |
| SENSE w/REG | 115.18 | 34.54 ± 2.41 (14.45%) | 22.81 | 6.84 ± 0.38 (24.06%) | 0.20 |
| Flyback EPSI | 116.03 | 37.20 ± 0.29 (9.10%) | 25.22 | 8.08 ± 0.17 (12.32%) | 0.22 |
| Symmetric EPSI | 109.87 | 35.32 ± 1.48 (9.52%) | 22.18 | 7.13 ± 0.53 (14.07%) | 0.21 |
| Symmetric w/ramps | 105.36 | 39.64 ± 1.39 (7.46%) | 20.95 | 7.88 ± 0.32 (14.12%) | 0.20 |