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Abstract #2603

Signal Considerations in Slicewise Dynamic B0 Shimming.

Saikat Sengupta1, E. Brian Welch1, John C. Gore1, Malcolm J. Avison1

1Radiology and Radiological Sciences, Vanderbilt University, Nashville, TN, United States

Dynamic Shimming improves Bo field homogeneity compared with global volume shimming. The most common approach for estimating slice-wise shim values involves removing the redundancy of functionally degenerate shim terms from an in-plane field regression and assuming a linear through plane inhomogeneity profile. This approach yields excellent inplane inhomogeneity compensation but compromises intravoxel signal recovery. Here, we present a slice-wise shim calculation method based on maximizing the voxel signal. Signal simulations and in vivo T2* measurements are presented which demonstrate improved signal recovery performance compared to both the degeneracy analysis and static global shimming approaches.

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Keywords

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