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Abstract #2569

Snapshot Field Monitoring Enables Correction of Slow Field Perturbations in High-Resolution Brain MRI

Signe Johanna Vannesjo1, Bertram J. Wilm1, Yolanda Duerst1, Benjamin E. Dietrich1, David Otto Brunner1, Christoph Barmet1, 2, Thomas Schmid1, Klaas P. Pruessmann1

1Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland; 2Skope Magnetic Resonance Technologies, Zurich, Switzerland

Breathing- and motion-related field fluctuations can affect brain imaging at 7T. The resulting artifacts can be reduced by concurrent field monitoring. However, gradient dephasing and signal decay of the field probes set limits to the image resolution. Here we assume the field perturbations to be slow, and thus a single field measurement per readout suffices for correction. It is shown that with this approach good image quality can be recovered in T2*-weighted images, that display strong ghosting when not corrected. Unlike full k-space monitoring, the approach is applicable also to high-resolution imaging.

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Keywords

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