Trirals for Imaging 10% Faster

Motivation: Designing hardware efficient trajectories is important for improving sampling efficiency, which can improve spatial encoding, mitigate off-resonance artifacts, and shorten echo times for diffusion sequences. Goal(s): To develop and characterize an imaging trajectory that fully utilizes the available gradient hardware. Approach: We propose using trirals, a triangular version of spiral trajectories, to fully utilize the available slew-rate on modern scanners. Results: Trirals show a theoretical decrease in readout time by 10%, while obtaining similar spatial encoding capabilities. We also demonstrate the use of variable density and mutli-shot trirals. Impact: Decreasing the readout time using trirals is important for time sensitive artifacts, such as field imperfections, and sequence TR/TE dependent signal changes.