Ashley Gould Anderson III1, Sebastian Gruhlke2, Oliver Wieben1,3, Michael Markl2,4
1Medical Physics, University of Wisconsin, Madison, WI, United States; 2Medical Physics, University Hospital Freiburg, Freiburg, Germany; 3Radiology, University of Wisconsin, Madison, WI, United States; 4Diagnostic Radiology, University Hospital Freiburg, Freiburg, Germany
Respiratory motion causes significant artifacts during 4D-Flow imaging in the torso due to long scan time requirements. Respiratory gating based on navigator signals or external measurements with bellows have been shown to reduce phase-related motion artifacts in long two- and three-dimensional free breathing acquisitions. Moreover, real-time adaptive k-space reordering, i.e. phase encoding based on the current position in the respiration cycle, can considerably improve navigator efficiency and thus reduce overall scan time. This work builds on proven respiratory gating and compensation methods by extending them to include reordering in the 3D slice-select direction in addition to the phase-encoding direction.