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Abstract #2761

Novel Method to Measure and Characterize Shim Induced Eddy Current Fields with Calibration Applications for Dynamic Shim Updating at 7T

Alex A. Bhogal1, Jos Koonen2, Jeroen Siero, Vincent Boer, Dennis Klomp, Peter Luijten, Hans Hoogduin

1Radiology, University Medical Center Utrecht, Utrecht, Netherlands; 2Philips

Dynamic Slice Based shimming at high field is gaining interest. Here, a novel method is presented to measure and characterize EC fields for pre-emphasis and eddy current compensation without the need for field probes or projection based measurements. Complete 3D datasets are acquired providing complete spatio-temporal characterization of eddy field self and cross terms up to third order. Results are used to calibrate a Dynamic Shim Updating (DSU) unit for slice-based applications at 7T.

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Keywords

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