Indirect Measurement of Echo Peak Shift for Half Echo Ultrashort TE (UTE) Imaging with Radial Sampling

Masahiro Takizawa¹, Hikaru Hanada¹, Kuniharu Oka¹, Tetsuhiko Takahashi¹

UTE sequence based on half echo radial sampling is very sensitive to small k-space trajectory errors. Many kind of gradient waveform approximation were developed for correcting these k-space trajectory errors. The remaining echo peak shift after applying the gradient waveform approximation causes image degradation. Because UTE sequence acquires only half the echo signal, it is difficult to detect echo peak position directly. We developed indirect echo peak detection algorithm dedicated for half echo signal by using pre-scan. The results shows that this indirect method works well and makes it possible to effectively minimize the error in the k-space trajectory.