Jan Ole Blumhagen1, 2, Ralf Ladebeck1, Matthias Fenchel1, Klaus Scheffler2, 3, Harald H. Quick4
1Magnetic Resonance, Siemens Healthcare, Erlangen, Bavaria, Germany; 2Division of Radiological Physics, University of Basel Hospital, Basel, Switzerland; 3MRC Department, Max Planck Institute for Biological Cybernetics, Tbingen, Germany; 4Institute of Medical Physics, Friedrich-Alexander-University Erlangen-Nrnberg, Erlangen, Germany
In whole-body MR/PET attenuation correction, an MR-based FoV extension is of emerging interest. However, gradient nonlinearities and B0 inhomogeneities often hamper an accurate spatial encoding at the edges of large FoVs. Recently, we proposed a method to axially extend the FoV by determining an optimal readout gradient field which locally compensates B0 inhomogeneities and gradient nonlinearities. In this work a combination of the mentioned axial FoV extension and Continuous Table Movement is presented. In experiments on volunteers a significant distortion reduction has been achieved at off-center positions of up to 300 mm off from the iso-center.
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