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Abstract #2493

Spin Echo and Adiabatic Spin Echo Motion Compensated Spiral Functional MRI

Priti Balchandani1, John M. Pauly2, Daniel M. Spielman1, Gary H. Glover1

1Radiology, Stanford University, Stanford, CA, United States; 2Electrical Engineering, Stanford Universiy, Stanford, CA, United States

We have developed spin echo and adiabatic spin echo motion compensated spiral fMRI sequences to isolate the small blood vessel contribution to the BOLD signal. The sequences provide improved immunity to B0-inhomogeneity and motion artifacts. The adiabatic version of the sequence utilizes matched phase adiabatic SLR pulses to provide a B1-insensitive spin echo. 3T phantom and in vivo functional scans show more uniform signal-to-fluctuation-noise ratio and higher resolution functional maps are achieved by the spin echo sequences when compared to a conventional gradient echo spiral fMRI sequence.

Keywords

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