Meeting Banner
Abstract #4155

Simultaneous Echo Refocused (SIR) EPI with Constant TE

An Thanh Vu1, 2, Audrey Chang1, 2, Liyong Chen1, 2, David Feinberg1, 2

1Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, United States; 2Advanced MRI Technologies, Sebastopol, CA, United States

Simultaneous echo refocused (SIR) EPI has greatly accelerated the acquisition of both fMRI and DTI data sets. However, the effective echo time (TE) of each individual SIR slice can differ by several milliseconds, resulting in slice dependent signal intensity and BOLD contrast. Here, we propose a constant TE version of the SIR method that is able to use TR specific phase correction navigators while maintaining the minimum TE and TR of the original SIR method. SIR with and without constant TE is evaluated in both phantom and human fMRI experiments.

Keywords

able accelerated acceleration accelerations acquisition added adjacent advanced best black blip block bold checkerboard circles collected colors combining comparing complicate concatenations conditions constant contrast correction correspondingly cross dependent design diagram differ earlier effective eliminates enable even evoked excitations expected flashing generates gradient greatly green healthy human implementation implemented imposing individual institute intensity introducing invalidates linear longer maintaining male match matrix milliseconds navigator navigators negative original otherwise paired pairs paradigm partial phantom plot plotted positive propose protocol pulse quantified reduces refocused regression remedy responses runs scatter section separately sets several significantly simultaneous slice slices slope slopes spherical statistical stronger student subject technologies though triangles trio variation version water year zero