Fig. 3.

T₁ estimation accuracy evaluated in the calibrated ISMRM/NIST phantom. Shown is a comparison between the true and measured compartment T₁ values for an optimized 8-measurement protocol (a) and an unoptimized 21-measurement protocol (b). The dashed line in each plot is the identity line whereas the red line is the least-squares fit line. The error bars represent the standard deviation of the measured T₁ values within the compartment. Note the larger bias in the 21-measurement protocol. The estimation error as a function of the reference phantom T₁ values are shown in (c) for the 8-measurement protocol and in (d) for the 21-measurement protocol.