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Abstract #2571

Autocalibrated PROPELLER-EPI: Intrinsic Geometric Distortion Correction Without Additional Reference Data

Martin Krmer1, Jrgen R. Reichenbach1

1Medical Physics Group, Institute of Diagnostic and Interventional Radiology I, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany

Novel reconstruction technique for PROPELLER-EPI which requires no additionally measured field map for distortion correction. By modulating the input data with constant frequency offsets the effective resonance frequency on which the image is reconstructed is modulated, enabling autocalibrated PROPELLER-EPI reconstruction. The theory of the technique is explained in detail including a proposed algorithm for automatic detection of on resonant image parts. We compare the proposed method to standard PROPELLER-EPI image reconstruction using statically measured field maps showing that comparable results can be achieved.

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Keywords

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