Figure 2: Simulation of T_1ρ relaxation curves and investigation of T_1ρ-weighted glucose contrast.

(a) Simulated T_1ρ relaxation curves for glucose concentrations of 5 mM and 20 mM and transversal relaxation rates R₂ = 15 s⁻¹, 20 s⁻¹ and 25 s⁻¹. (b) Signal difference ΔS between the relaxation curves (solid lines) and our analytical approximation (Eq. 3, dotted lines) as a function of the spin-lock time TSL. The dashed vertical line at TSL = 50 ms marks the suggested value yielding the best contrast-to-noise ratio. (c) The proposed contrast ΔS_rel as function of the glucose concentration change Δc_Glc for R₂ = 15 s⁻¹ (solid blue line) and R₂ = 25 s⁻¹ (green diamonds) for constant TSL = 50 ms. Note the linearity in Δc_Glc and the independence of absolute relaxation rates.