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.