Interleaved ultrashort echo acquisition for motion-robust bicomponent imaging of cortical bone

Motivation: Acquiring a series of images with different echo times for short T2 tissues usually requires separate scans using ultrashort echo sequences due to the need for short echo spacings. These separate scans are often susceptible to motion artifacts, necessitating post-acquisition motion correction. Goal(s): To develop a new motion-insensitive sequence that captures different echo images within a single scan. Approach: We developed an interleaved multi-echo sequence with flexible echo spacing, investigating it on the tibial cortical bone of healthy subjects for bicomponent T2* imaging. Results: This new sequence provided more reliable bicomponent T2* measurements than conventional separate acquisitions. Impact: The proposed sequence enables motion-insensitive quantitative imaging of short T2 tissues requiring multi-echo acquisitions, such as bi-component T2* imaging and quantitative susceptibility mapping, without post-acquisition motion correction.