Abstract #1169

High-resolution segmented-accelerated EPI using Variable Flip Angle FLEET with tailored slice profiles

Avery JL Berman ^1,2, Thomas Witzel^1,2, William A Grissom ^3,4, Daniel Park ¹, Kawin Setsompop^1,2,5, and Jonathan R. Polimeni^1,2,5

¹Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Boston, MA, United States, ²Department of Radiology, Harvard Medical School, Boston, MA, United States, ³Vanderbilt University Institute of Imaging Science, Nashville, TN, United States, ⁴Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, United States, ⁵Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, United States

New evidence suggests that fMRI has spatial specificity at scales far below current voxel sizes, but encoding limits preclude single-shot EPI at sufficient spatial resolution. Segmented EPI can help overcome these limits, but is well-known to be temporally unstable. Here we propose a reordering of the EPI segments, known as FLEET, combined with variable progression of flip angles to maximize the image signal level and a tailored RF pulse design to maintain compatible slice profiles. We demonstrate that this approach provides stable segmented EPI acquisitions with negligible ghosting, and when combined with acceleration can provide submillimeter fMRI acquisitions at 3T.

How to access this content:

For one year after publication, abstracts and videos are only open to registrants of this annual meeting. Registrants should use their existing login information. Non-registrant access can be purchased via the ISMRM E-Library.

After one year, current ISMRM & ISMRT members get free access to both the abstracts and videos. Non-members and non-registrants must purchase access via the ISMRM E-Library.

After two years, the meeting proceedings (abstracts) are opened to the public and require no login information. Videos remain behind password for access by members, registrants and E-Library customers.

Click here for more information on becoming a member.