Signal Amplitude Dependence on Object Size and Shape Due to T2 Decay During Radial K-Space Readout in Ultrashort TE Sequences: A 2D Ring Model.

Jing-Tzyh Alan Chiang¹, Michael Carl², Jiang Du¹, Graeme Bydder¹

We investigate the signal amplitude relationships due to T2 decay during radial k-space readout in ultrashort TE sequences, via numerical simulations on 2D rings of varying inner and outer diameters. Decreasing inner and increasing outer diameters lead to increased signal amplitudes at any given T2 value, which demonstrate important dependencies of signal amplitude on object shape and size. These results on 2D rings also serve as numerical models for analyzing T2 dependent signal and contrast in quantitative UTE techniques that utilize axial imaging of tubular bones, such as in cortical bone water quantification.