Simulated single-voxel spectroscopic data combined by (a) ESPIRiT method, (b) RefPeak method, (c) SVD method, and (d) SOS method at a representative noise with nominal pyruvate SNR of 57. (e) and (f) shows the normalized magnitude spectra and spectral phase compared to simulation ground truth. Lactate-to-pyruvate ratio without baseline subtraction (g) was quantified for each coil combination method as a function of pyruvate SNR. Each box encloses the 25th-75thpercentile, while the ground truth is denoted by the dashed black line. For simplicity outliers are not shown. Note the overestimation of the SOS reconstruction, even at high SNR. Simulation results with baseline subtraction can be found in Supplementary Figure 2.
*Denotes significant difference (p < 0.05) from the ground truth.