Figure 4.
Reproducibility in 3 healthy subjects. (A–C) Isolated CEST effects obtained from 3‐pool Lorentzian fitting of the MTRLD spectrum (Equations (6) and (7)). Whole‐brain images are provided in Supporting Information Figure S12. The +2.0‐ppm signal is strongly influenced by direct water saturation and residual off‐resonance effects. (D,E) Mean MTRLD spectra in gray and white matter segments. (F) Mean and standard deviation across subjects of fitted CEST effects in gray and white matter segments of a single slice. Slices were selected to have similar gray and white matter segments for each subject. Gray matter and white matter signals are clearly distinguishable for the +3.5‐ppm, –3.5‐ppm, and ssMT pools, with coefficient of variation for each pool and each ROI printed above each bar. MTRLD spectra and fitted pool amplitudes are expressed in arbitrary units