Influence of absolute concentration corrections other than for reciprocity deviations on the relative absolute concentrations of 4 major metabolites averaged in healthy control subjects (n = 14)
Variable | Cho, % | Cr, % | NAA, % | NAA+NAAG, % |
---|---|---|---|---|
With reciprocity | 100.0 | 100.0 | 100.0 | 100.0 |
Coefficient of variance | 13.5 | 9.3 | 11.6 | 12.3 |
Flip angle correction | 93.2 | 94.7 | 94.2 | 93.7 |
+ CSF | 97.7 | 99.2 | 98.7 | 98.2 |
+ Differential T2 | 104.0 | 109.7 | 102.8 | 102.3 |
+ Boltzmann | 108.2 | 114.1 | 107.0 | 106.4 |
Note:—The top row 100% represents the concentrations without any correction other than the reciprocity correction. Subsequent rows show the accumulated effect of additional quantification step on the concentration values. Fully corrected relative values are shown in the last row. Cho indicates choline; Cr, creatine; NAA, N-acetylaspartate; NAAG, N-acetyl aspartylglutamate.