Mario Bacher1,2, Barbara Dornberger2, Jan Bollenbeck2, Matthias Stuber1, and Peter Speier2
1Department of Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland, 2Siemens Healthcare Magnetic Resonance, Erlangen, Germany
1Department of Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland, 2Siemens Healthcare Magnetic Resonance, Erlangen, Germany
Electromagnetic simulations of the Pilot Tone navigator are presented which can be used to better understand the complex location dependent characteristics of the received motion signals.
Figure 1: Geometry
of the virtual phantom: The volume “Field sensor volume” was
voxelized at $$$0.8\,mm$$$ isotropic resolution. Voxel size outside this volume was increased automatically where
possible. The generator loop is labeled as a white circle. The
blue plane represents the analysis plane $$$\Sigma_{ant}$$$. Red and green circles show the location of
virtual coils $$$L_{R1}$$$ and $$$L_{R2}$$$ used in
the further analysis. Boundary volume was set automatically to $$$(1366\times1217\times1250)\,mm^3$$$ using uniaxially perfectly matched layer (UPML) condition.
Figure 2: Cardiac
volume ground truth (a) and simulated received time-signals $$$u[t_n]$$$ in the virtual coils $$$L_{R1}$$$ (b) and $$$L_{R2}$$$ (c) plotted as modulation depth, i.e. change
relative to the mean signal in percent. The approximate position of ECG R-peak
is shown in orange in (a). Black arrows in (a) show periods of contraction
(systole) and expansion (diastole) in the cardiac volume curve.
