Dana C. Peters1,
Leo K. Tam1, Gigi Galiana2, Robert Todd Constable2
1Diagnostic
Radiology, Yale Medical School, New Haven, CT, United States; 2Diagnostic
Radiology, Yale University, New Haven, CT, United States
In O-space, the z2 non-linear gradient generates a quadratic field, which at the center-placement, CP, has a very low effective magnetic field gradient (i.e Hz/pixel). Therefore off-resonant spins in the CP location will be inaccurately encoded based on their frequency. Here we explore the effects of off-resonant signal on O-space. The reconstruction was modified, based on the insight that the spatial encoding magnetic field has little information, and significant off-resonance error, in the location around the CP. In the modified ART reconstruction, for each CP, the image estimate in the neighborhood of the CP is not updated. Simulations show improvement.
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