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Abstract #0409

Blipped-CAIPI Spiral for Simultaneous Multi-Slice BOLD FMRI

Benjamin Zahneisen1, Benedikt A. Poser1, Thomas Ernst2, Victor Andrew Stenger1

1Department of Medicine, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States; 2Department of Medicine, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI, United States

Sub-second whole brain fMRI is advantageous since it resolves physiological signal fluctuations, virtually freezes head motion, has greater statistical power, and allows the detection of subtle HRF shifts or delays. Recently, the blipped-CAIPI EPI method was introduced as a means to reduce the g-factor penalty in simultaneous multi-slice (SMS) imaging. However, the approach is limited to Cartesian trajectories with their unique fold-over artifact. Here, we present a new framework for SMS imaging based on 3D Fourier encoding of simultaneously excited slices. We show that the blipped-CAIPI approach can be generalized to non-Cartesian trajectories and SENSE-like reconstructions including a new design for blipped-CAIPI spiral trajectories. Spiral has a more efficient gradient utilization and shorter readouts are possible.

Keywords

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