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Abstract #2562

On the Relation of the Ripple Artifact in Multi-Spectral Imaging and Susceptibility Induced Field Gradients

Chiel J. den Harder1, Ulrike A. Blume2, Gert van IJperen1, Clemens Bos3

1MRI Technology Development, Philips, Best, Noord Brabant, Netherlands; 2Imaging Systems, Philips, Hamburg, Germany; 3Image Sciences Institute, University Medical Center Utrecht, Utrecht, Netherlands

Multi-Spectral Imaging (MSI) techniques have been shown to significantly reduce susceptibility artifacts. Especially in techniques that use gradient selection, such as Slice Encoding for Metal Artifact Correction (SEMAC), remaining ripple artifacts can be prominent. This work presents a simulation analysis verified by phantom experiments, showing that the ripple artifact appears only if B0 varies both in-plane and through-plane. As shown before, the ripple artifact is the remaining limitation of the capability of MSI techniques to reduce metal artifacts. The simulations presented here help define the origin of the ripple artifact and provide a means to investigate ways to address it.

Keywords

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