Figure 1a:

Diagrams of UTE sequences used for (a) bulk BWC and (b) SR measurements. (a) A three-dimensional hybrid radial UTE sequence involving radial readout with ramp sampling for the k_x and k_y axes and variable echo time (TE) on the k_z axis was used to achieve minimal echo time for k_z = 0. (b) A two-dimensional long-T2-suppressed UTE sequence was used for quantifying SR. Dashed box = magnetization preparation portion for long-T2 suppression, which consisted of either a dual-band or an adiabatic inversion pulse followed by a spoiler gradient before standard UTE acquisition. ACQ = data acquisition, G_x = x-gradient, G_y = y-gradient, G_z = z-gradient, RF = radiofrequency, VERSE = variable-rate selective excitation.