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Abstract #2382

Gradient-Modulated SWIFT

Jinjin Zhang1, 2, Djaudat Idiyatullin1, Curtis Andrew Corum1, Naoharu Kobayashi1, Michael Garwood1

1Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN, United States; 2Department of Physics, University of Minnesota, Minneapolis, MN, United States

We report Sweep Imaging with Fourier Transformation (SWIFT) using time varying gradients during excitation. Gradient-modulated offset independent adiabaticity (GOIA) approach was used to modify the pattern of the RF pulse. Linear response theory was used to derive the signal evolution. A specific correlation method to retrieve the spin density for this case was developed. This method greatly increases the versatility of the SWIFT method and allows, for example, RF power reduction and increasing of the effective acquisition bandwidth. These conclusions are supported by simulations, resolution phantom experiments, and imaging of human brain in vivo using different types of gradient modulation.

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Keywords

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