3D UTE With Twisted Trajectories

Motivation: Radial UTE can often be impacted by aliasing artifacts if undersampling is required to achieve a short scantime. More efficient trajectories may alleviate these limitations. Goal(s): Our goal is to study how much aliasing reduction can be achieved in UTE MRI by applying a small amount of spiral twist to the readout trajectory. Approach: In order to add some twist/spiral to the UTE trajectories, we simply added an orthogonal gradient while simultaneously ramping down the radial-out read gradient. Results: Images using a longer, twisted readout trajectory results in less visible aliasing artifacts and increased SNR. Impact: UTE MRI undersampling artifacts were found to be reduced using simple twisted k-space trajectories, hence allowing a reduction in scantime.