Abstract #0635

Multiplexed Echo Planar Imaging with Sub-Second Whole Brain FMRI & Fast Diffusion Imaging

David A. Feinberg^1,2, Steen Moeller³, Stephen Smith⁴, Edward Auerbach³, Kamil Ugurbil³, Essa Yacoub³

¹Advanced MRI Technologies, Sebastopol, CA, USA; ²University of California, Berkeley & San Francisco, CA, USA; ³Center for Magnetic Resonance Research, University of Minnesota; ⁴FMRIB, Oxford University

A multiplexed-EPI (M-EPI) pulse sequence is presented that combines temporal multiplexing (m) utilizing simultaneous echo refocused (SIR) EPI and spatial multiplexing (n) with multibanded RF pulses (MB) to achieve m x n images in an EPI echo train. This resulted in significant increases in temporal resolution for whole brain fMRI evaluated at 0.8s and 0.4s TR in resting state and in substantial reductions in scan time 8.5m in HARDI neuronal fibertracks using 256 b-values. Multiplexed EPI can be used to acquire higher spatial resolutions, increase diffusion encoding, or to investigate temporal dynamics of the fMRI response.