title: Development and evaluation of TWIST Dixon for dynamic contrast-enhanced (DCE) MRI with improved acquisition efficiency and fat suppression.
abstract: OBJECTIVE
  To develop a new pulse sequence called time-resolved angiography with stochastic trajectories (TWIST) Dixon for dynamic contrast enhanced magnetic resonance imaging (DCE-MRI).
  
  
  METHODS
  The method combines dual-echo Dixon to generate separated water and fat images with a k-space view-sharing scheme developed for 3D TWIST. The performance of TWIST Dixon was compared with a volume interpolated breathhold examination (VIBE) sequence paired with spectrally selective adiabatic inversion Recovery (SPAIR) and quick fat-sat (QFS) fat-suppression techniques at 3.0T using quantitative measurements of fat-suppression accuracy and signal-to-noise ratio (SNR) efficiency, as well as qualitative breast image evaluations.
  
  
  RESULTS
  The water fraction of a uniform phantom was calculated from the following images: 0.66 ± 0.03 for TWIST Dixon; 0.56 ± 0.23 for VIBE-SPAIR, and 0.53 ± 0.14 for VIBE-QFS, while the reference value is 0.70 measured by spectroscopy. For phantoms with contrast (Gd-BOPTA) concentration ranging from 0-6 mM, TWIST Dixon also provides consistently higher SNR efficiency (3.2-18.9) compared with VIBE-SPAIR (2.8-16.8) and VIBE-QFS (2.4-12.5). Breast images acquired with TWIST Dixon at 3.0T show more robust and uniform fat suppression and superior overall image quality compared with VIBE-SPAIR.
  
  
  CONCLUSIONS
  The results from phantom and volunteer evaluation suggest that TWIST Dixon outperforms conventional methods in almost every aspect and it is a promising method for DCE-MRI and contrast-enhanced perfusion MRI, especially at higher field strength where fat suppression is challenging.
authors.affiliation: Department of Radiology and Imaging Science, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Le
authors.forename: Randall
authors.initials: R
authors.lastname: Kroeker
authors.forename: Hal D
authors.initials: HD
authors.lastname: Kipfer
authors.forename: Chen
authors.initials: C
authors.lastname: Lin
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology*; D000465:Algorithms; D001940:Breast / Q000033:anatomy & histology*; D003287:Contrast Media; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique
chemical_list: D003287:Contrast Media