General Time-Encoding Description and Improved RASER Imaging

Ryan Chamberlain¹, Michael Garwood¹

RASER provides purely T₂-weighted single-shot images that show promise for fMRI studies in areas of the brain that are difficult to image with EPI. The basis of RASER is time-encoding. In this work, we provide a general description of time-encoding for any excitation pulse with frequency and gradient modulation, along with an analysis of the SNR possible with time-encoding, and a comparison of the time-encoded signal produced by chirp, HS20, and HS40 pulses.