title: Improved fat water separation with water selective inversion pulse for inversion recovery imaging in cardiac MRI.
abstract: OBJECTIVE
  To develop an improved chemical shift-based water-fat separation sequence using a water-selective inversion pulse for inversion recovery 3D contrast-enhanced cardiac magnetic resonance imaging (MRI).
  
  
  METHODS
  In inversion recovery sequences the fat signal is substantially reduced due to the application of a nonselective inversion pulse. Therefore, for simultaneous visualization of water, fat, and myocardial enhancement in inversion recovery-based sequences such as late gadolinium enhancement imaging, two separate scans are used. To overcome this, the nonselective inversion pulse is replaced with a water-selective inversion pulse. Imaging was performed in phantoms, nine healthy subjects, and nine patients with suspected arrhythmogenic right ventricular cardiomyopathy plus one patient for tumor/mass imaging. In patients, images with conventional turbo-spin echo (TSE) with and without fat saturation were acquired prior to contrast injection for fat assessment. Subjective image scores (1 = poor, 4 = excellent) were used for image assessment.
  
  
  RESULTS
  Phantom experiments showed a fat signal-to-noise ratio (SNR) increase between 1.7 to 5.9 times for inversion times of 150 and 300 msec, respectively. The water-selective inversion pulse retains the fat signal in contrast-enhanced cardiac MR, allowing improved visualization of fat in the water-fat separated images of healthy subjects with a score of 3.7 ± 0.6. Patient images acquired with the proposed sequence were scored higher when compared with a TSE sequence (3.5 ± 0.7 vs. 2.2 ± 0.5, P < 0.05).
  
  
  CONCLUSIONS
  The water-selective inversion pulse retains the fat signal in inversion recovery-based contrast-enhanced cardiac MR, allowing simultaneous visualization of water and fat.
authors.affiliation: Department of Medicine, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA.
authors.forename: Lukas
authors.initials: L
authors.lastname: Havla
authors.forename: Tamer
authors.initials: T
authors.lastname: Basha
authors.forename: Hussein
authors.initials: H
authors.lastname: Rayatzadeh
authors.forename: Jaime L
authors.initials: JL
authors.lastname: Shaw
authors.forename: Warren J
authors.initials: WJ
authors.lastname: Manning
authors.forename: Scott B
authors.initials: SB
authors.lastname: Reeder
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kozerke
authors.forename: Reza
authors.initials: R
authors.lastname: Nezafat
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology*; D000465:Algorithms; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000295:instrumentation / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014867:Water / Q000032:analysis*
chemical_list: D014867:Water