title: Multilattice sampling strategies for region of interest dynamic MRI.
abstract: A multilattice sampling approach is proposed for dynamic MRI with Cartesian trajectories. It relies on the use of sampling patterns composed of several different lattices and exploits an image model where only some parts of the image are dynamic, whereas the rest is assumed static. Given the parameters of such an image model, the methodology followed for the design of a multilattice sampling pattern adapted to the model is described. The multi-lattice approach is compared to single-lattice sampling, as used by traditional acceleration methods such as UNFOLD (UNaliasing by Fourier-Encoding the Overlaps using the temporal Dimension) or k-t BLAST, and random sampling used by modern compressed sensing-based methods. On the considered image model, it allows more flexibility and higher accelerations than lattice sampling and better performance than random sampling. The method is illustrated on a phase-contrast carotid blood velocity mapping MR experiment. Combining the multilattice approach with the KEYHOLE technique allows up to 12× acceleration factors. Simulation and in vivo undersampling results validate the method. Compared to lattice and random sampling, multilattice sampling provides significant gains at high acceleration factors.
authors.affiliation: Institute for Digital Communications (IDCOM) & Joint Research Institute for Signal and Image Processing, School of Engineering, University of Edinburgh, Alexander Graham Bell Building, The King's Buildings, Mayfield Road, Edinburgh, UK. g.rilling@ed.ac.uk
authors.forename: Gabriel
authors.initials: G
authors.lastname: Rilling
authors.forename: Yuehui
authors.initials: Y
authors.lastname: Tao
authors.forename: Ian
authors.initials: I
authors.lastname: Marshall
authors.forename: Mike E
authors.initials: ME
authors.lastname: Davies
mesh_terms: D000465:Algorithms; D017536:Carotid Artery, Common / Q000033:anatomy & histology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D015203:Reproducibility of Results; D018401:Sample Size; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted