How To
Parallel Imaging
Parallel Imaging
The GE version of parallel imaging, ASSET, is now available for use withBack to Top
functional EPI on both 3T scanners. The ASSET protocols are saved under Head ->
Advanced_fMRI. Note, that a 6 sec ASSET calibration scan needs to be performed
before ASSET-enabled EPI can be run.
Advantages of ASSET EPI include faster acquisition and hence a greater maximum
slice acquisition rate (>= 20/sec under certain parameter settings). Thus,
ASSET EPI can be used to improve spatiotemporal resolution or brain coverage
(e.g. for event related studies that require short TR and full brain coverage).
In addition, ASSET EPI affords substantially shorter TE values thus improving
signal in brain areas affected by susceptibility artifacts (e.g. orbitofrontal
and medial temporal lobes). However, the tradeoffs include somewhat lesser SNR
and substantially lagging image reconstruction for high slice rates (note that
scanning is not possible while images are being reconstructed).
In addition, spatial blurring of EPI images can now be easily controlled by
changing Fermi Filter settings in User CV window. A protocol with the
minimum-blurring settings (Fermi Filter off) is saved under Advanced_fMRI.
If you would like a brief tutorial on how to use these new EPI imaging options,
please contact kunlu@ucsd.edu
