Fig. 3

Fit (red) of the same data (white) calculated with protocol 5 resulting in a “flat” (a) and with protocol 18 with a “less flat” difference line (green) (b). The baseline is orange. χ² calculated by the post processing software was 3348 (a) and 5122 (b), respectively and is a little less than the mean values of Table 3. Image (c) shows the distorted Naa evaluation with NaaG as additional metabolite. A:, P: and W: are the amplitude of a metabolite, its frequency in ppm and its line width in Hz. Note: the lipid amplitudes inside healthy brain tissue are very small compared to that of tumors. In most cases, depending on the protocol, no or only one lipid line was detected. This is also documented by both protocols with the best reproducibility (protocol 14 and 18), which did not use lipid models