Figure 8.

Comparison of the correction performance of the proposed dynamic methods CEST‐GRE‐2TE (rows 1 and 2) and NAV‐EPI‐2TE (rows 3 and 4) for subjects V1‐V5: ∆B ₀‐corrected MTR_asym (0.3–1.0 ppm) maps in the absence (first and third rows) and in the presence (second and fourth rows) of the induced B ₀ drift during each CEST measurement. A ROI along each volunteer's brain border was manually drawn (delineated in black) and the MTR_asym mean ± standard deviation values within this ROI are shown at the bottom of each map. Among the dynamic methods, both CEST‐GRE‐2TE and NAV‐EPI‐2TE generated highly consistent MTR_asym contrasts between scans in all cases. CEST‐GRE‐2TE, chemical exchange saturation transfer‐gradient echo‐2TE; MTR_asym, asymmetric magnetization transfer ratio; NAV‐EPI‐2TE, navigator‐echoplanar imaging‐2TE