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Abstract #3388

Retrospective Image Correction in the Presence of Temporal Magnetic Field Changes Using SENSE Navigator Echoes

Maarten J. Versluis1, 2, Bradley P. Sutton3, Paul W. de Bruin1, Peter Boernert, 24, Andrew G. Webb1, 2, Matthias J.P. van Osch1, 2

1Radiology, Leiden University Medical Center, Leiden, Netherlands; 2C.J. Gorter Center for high field MRI, Leiden University Medical Center, Leiden, Netherlands; 3Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Champaign, IL, United States; 4Research Europe, Philips, Hamburg, Germany

Spatio-temporal magnetic field changes in the brain caused by breathing or body movements can lead to image artifacts. This is especially a problem in high magnetic field T2*-weighted sequences. By acquiring a navigator echo using multiple receive channels and their respective coil sensitivity profiles the spatially varying magnetic field was estimated, termed SENSE navigators. A retrospective reconstruction framework was implemented in Matlab using an iterative conjugate gradient solver. Compared to a simple zeroth order navigator the SENSE navigator technique lead to a significant reduction of image artifacts.

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Keywords

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