title: MRXCAT: Realistic numerical phantoms for cardiovascular magnetic resonance.
abstract: BACKGROUND
  Computer simulations are important for validating novel image acquisition and reconstruction strategies. In cardiovascular magnetic resonance (CMR), numerical simulations need to combine anatomical information and the effects of cardiac and/or respiratory motion. To this end, a framework for realistic CMR simulations is proposed and its use for image reconstruction from undersampled data is demonstrated.
  
  
  METHODS
  The extended Cardiac-Torso (XCAT) anatomical phantom framework with various motion options was used as a basis for the numerical phantoms. Different tissue, dynamic contrast and signal models, multiple receiver coils and noise are simulated. Arbitrary trajectories and undersampled acquisition can be selected. The utility of the framework is demonstrated for accelerated cine and first-pass myocardial perfusion imaging using k-t PCA and k-t SPARSE.
  
  
  RESULTS
  MRXCAT phantoms allow for realistic simulation of CMR including optional cardiac and respiratory motion. Example reconstructions from simulated undersampled k-t parallel imaging demonstrate the feasibility of simulated acquisition and reconstruction using the presented framework. Myocardial blood flow assessment from simulated myocardial perfusion images highlights the suitability of MRXCAT for quantitative post-processing simulation.
  
  
  CONCLUSIONS
  The proposed MRXCAT phantom framework enables versatile and realistic simulations of CMR including breathhold and free-breathing acquisitions.
authors.affiliation: Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, Zurich, 8092, Switzerland. wissmann@biomed.ee.ethz.ch.
authors.forename: Lukas
authors.initials: L
authors.lastname: Wissmann
authors.affiliation: Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, Zurich, 8092, Switzerland. santelli@biomed.ee.ethz.ch.|Division of Imaging Sciences & Biomedical Engineering, King's College London, London, UK. santelli@biomed.ee.ethz.ch.
authors.forename: Claudio
authors.initials: C
authors.lastname: Santelli
authors.affiliation: Department of Radiology, Carl E Ravin Advanced Imaging Laboratories, The Duke University Medical Center, Durham, USA. paul.segars@duke.edu.
authors.forename: William P
authors.initials: WP
authors.lastname: Segars
authors.affiliation: Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, Zurich, 8092, Switzerland. kozerke@biomed.ee.ethz.ch.|Division of Imaging Sciences & Biomedical Engineering, King's College London, London, UK. kozerke@biomed.ee.ethz.ch.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kozerke
mesh_terms: D062485:Breath Holding; D055424:Cardiac-Gated Imaging Techniques / Q000295:instrumentation*; D003198:Computer Simulation; D003326:Coronary Circulation; D005240:Feasibility Studies; D006339:Heart Rate; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000295:instrumentation*; D008955:Models, Cardiovascular; D055414:Myocardial Perfusion Imaging / Q000295:instrumentation*; D009716:Numerical Analysis, Computer-Assisted; D019047:Phantoms, Imaging; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012985:Software Design