title: Fat ViP MRI: Virtual Phantom Magnetic Resonance Imaging of water-fat systems.
abstract: Virtual Phantom Magnetic Resonance Imaging (ViP MRI) is a method to generate reference signals on MR images, using external radiofrequency (RF) signals. The aim of this study was to assess the feasibility of ViP MRI to generate complex-data images of phantoms mimicking water-fat systems.
  
  
  
  Various numerical phantoms with a given fat fraction, T2* and field map were designed. The k-space of numerical phantoms was converted into RF signals to generate virtual phantoms. MRI experiments were performed at 4.7T using a multi-gradient-echo sequence on virtual and physical phantoms. The data acquisition of virtual and physical phantoms was simultaneous. Decomposition of the water and fat signals was performed using a complex-based water-fat separation algorithm.
  
  
  
  Overall, a good agreement was observed between the fat fraction, T2* and phase map values of the virtual and numerical phantoms. In particular, fat fractions of 10.5±0.1 (vs 10% of the numerical phantom), 20.3±0.1 (vs 20%) and 30.4±0.1 (vs 30%) were obtained in virtual phantoms.
  
  
  
  The ViP MRI method allows for generating imaging phantoms that i) mimic water-fat systems and ii) can be analyzed with water-fat separation algorithms based on complex data.
authors.affiliation: INSERM, UMR 1099, Rennes, F-35000, France; Université de Rennes 1, LTSI, Rennes, F-35000, France. Electronic address: roberto.salvati@univ-rennes1.fr.
authors.forename: Roberto
authors.initials: R
authors.lastname: Salvati
authors.affiliation: INSERM, UMR 1099, Rennes, F-35000, France; Université de Rennes 1, LTSI, Rennes, F-35000, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Hitti
authors.affiliation: INSERM, UMR 1099, Rennes, F-35000, France; Université de Rennes 1, LTSI, Rennes, F-35000, France.
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Bellanger
authors.affiliation: INSERM, UMR 1099, Rennes, F-35000, France; Université de Rennes 1, LTSI, Rennes, F-35000, France; CRLCC, Centre Eugène Marquis, Rennes, F-35000, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Saint-Jalmes
authors.affiliation: INSERM, UMR 1099, Rennes, F-35000, France; Université de Rennes 1, LTSI, Rennes, F-35000, France.
authors.forename: Giulio
authors.initials: G
authors.lastname: Gambarota
mesh_terms: D000465:Algorithms; D005223:Fats; D005240:Feasibility Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D014867:Water
chemical_list: D005223:Fats; D014867:Water
keywords: Fat quantification; MRI; Phase map; ViP MRI; Virtual Phantom