T2 Contrast Due to Signal Decay During Radial Readout in UTE (Ultrashort TE) Sequences

Jing-Tzyh Alan Chiang¹, Michael Carl², Jiang Du¹, Mark Bydder¹, Nick Szeverenyi¹, Robert F. Mattrey¹, Graeme Bydder¹

When imaging short T2 objects using ultrashort TE (UTE) pulse sequences, significant T2 decay can occur during radial readout for T2s comparable or less than the readout duration (typically ~1 ms), leading to signal amplitude loss in the image. Here, we study the relationship between T2 and the amount of signal amplitude loss i.e. T2 contrast due to signal decay during radial readout in UTE. Significant T2 contrast is present, especially for T2s in the 0.1 to 1 millisecond range. We also observe important dependencies of this T2 contrast on object size as well as gradient parameters.