Open EPTI: pluggable, distortion-free continuous readout developed on vendor-neutral Pulseq for versatile multi-contrast MR imaging

Motivation: EPTI provides an efficient, distortion-free readout, offering spatiotemporal resolutions comparable to EPI while addressing its limitations, which can be beneficial for various multi-contrast applications. Goal(s): In line with open-science and acquisition harmonization efforts, we aim to develop EPTI in open-source, vendor-neutral sequence/reconstruction platforms. Approach: We developed both multi-shot and single-shot EPTI in Pulseq with streamlined reconstruction in Gadgetron/BART, and demonstrated Pulseq-EPTI readout in three contrast acquisitions: i) quantitative MRI through GE-SE EPTI; ii) fMRI using GE-EPTI; iii) metabolic CEST imaging using CEST-prepared EPTI. Results: Pulseq-EPTI provides a pluggable, distortion-free readout module, enabling efficient qMRI, fMRI, and CEST imaging. Impact: We developed EPTI into vendor-neutral sequence/reconstruction frameworks, providing a pluggable, distortion-free readout for multi-contrast MR imaging. As proof-of-concept, we demonstrated Pulseq-EPTI readout in three contrast acquisitions tailored to three different applications, including quantitative MRI, fMRI, and CEST imaging.