Figure 4: Comparison of different metrics for CEST-based DGE-MRI by means of Bloch-McConnell simulations.
From: Fast and Quantitative T1ρ-weighted Dynamic Glucose Enhanced MRI
The metric ΔS = (Sref − S)/S0 and, contrary to T1ρ-w DGE-MRI, also the metric ΔSrel = (Sref − S)/Sref show a dependency on relaxation times T1 and T2 in the case of CEST-based DGE-MRI (a–d). However, employing R1 = 1/T1 and the apparent exchange-dependent relaxation evaluation AREX = (S0/Sref − S0/S) · R1 also CEST-based DGE-MRI yields a relaxation independent contrast. The simulated CEST pre-saturation parameters were chosen similar to Xu et al.9: 32 sinc-gauss pulses (50 ms, Δω = 1.2 ppm, B1 = 1.96 μT, separated by a 25 ms delay, each) and a delay of 2 s after each scan. The water and solute pool parameters were chosen similar to the CESL simulations in Fig. 2.
