Figure 4. Sampling-dependent aSNR and $\text{a}{\mathrm{T}}_2\mathrm{*}$ Changes across Phantom Matrix Sizes.

Sampling level vs percent difference in apparent signal-to-noise ratio (aSNR) (a) and $\text{a}{\mathrm{T}}_2\mathrm{*}$ (d) in 64³ phantom. Maximum percent difference for both metrics occurred at 10% sampling, where ΔaSNR decreased by 23.9% and $\Delta \text{a}{\mathrm{T}}_2\mathrm{*}$ increased by 3.2%. The 64³ phantom showed significant divergence (p < 0.05, vertical dashed line) in $\text{a}{\mathrm{T}}_2\mathrm{*}$ values from fully sampled images below 20% sampling. Sampling level vs percent difference in aSNR (b) and $\text{a}{\mathrm{T}}_2\mathrm{*}$ (e) in 96³ phantom. The maximum percent difference was also at 10% sampling, where ΔaSNR decreased by 17.0% and $\Delta \text{a}{\mathrm{T}}_2\mathrm{*}$ increased by 4.7%. The 96³ phantom showed significant divergence (p < 0.05, vertical dashed line) in $\text{a}{\mathrm{T}}_2\mathrm{*}$ values from fully sampled images below 60% sampling. Lastly, sampling level vs percent difference in aSNR (c) and $\text{a}{\mathrm{T}}_2\mathrm{*}$ (f) in 128³ phantom. The maximum percent difference was again at 10% sampling where ΔaSNR decreased by 13.5% and $\Delta \text{a}{\mathrm{T}}_2\mathrm{*}$ increased by 4.6%. The 128³ phantom showed significant divergence (p < 0.05, vertical dashed line) in $\text{a}{\mathrm{T}}_2\mathrm{*}$ values from fully sampled images below 80% sampling.