title: High-spatial-resolution three-dimensional MR cholangiography using a high-sampling-efficiency technique (SPACE) at 3T: comparison with the conventional constant flip angle sequence in healthy volunteers.
abstract: OBJECTIVE
  To evaluate the image quality of high-spatial-resolution three-dimensional magnetic resonance cholangiography (MRC) with a high-sampling-efficiency technique (sampling perfection with application optimized contrasts using different flip angle evolutions [SPACE]) in comparison with a conventional constant flip angle (FA) sequence at 3T.
  
  
  METHODS
  Eighteen volunteers were examined on a 3T MR unit using MRC imaging performed with three different free-breathing three-dimensional T2-weighted turbo spin-echo (TSE) sequences: 1) SPACE (spatial resolution, 1.1x1.0x0.84 mm), 2) constant FA (1.1x1.0x0.84 mm), and 3) SPACE at a higher resolution (SPACE HR; 1.0x0.9x0.644 mm). A five-point scale was used to compare overall image quality and visualization of the third branches of the bile duct (B2, B6, and B8). Depictions of cystic duct insertion and the highest order of bile duct visible were also compared.
  
  
  RESULTS
  MRC with SPACE and SPACE HR sequences produced significantly better overall image quality than the constant FA sequence. In all analyses of duct visibility, SPACE and SPACE HR sequences showed higher scores than the constant FA sequence.
  
  
  CONCLUSIONS
  High-resolution three-dimensional MRC with SPACE at 3T allows high-quality imaging of the biliary tract, and has the ability to depict nondilated intrahepatic bile ducts (IHBD) in healthy volunteers.
authors.affiliation: Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University Kyoto, Japan. arizono@kuhp.kyoto-u.ac.jp
authors.forename: Shigeki
authors.initials: S
authors.lastname: Arizono
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Isoda
authors.forename: Yoji S
authors.initials: YS
authors.lastname: Maetani
authors.forename: Yuusuke
authors.initials: Y
authors.lastname: Hirokawa
authors.forename: Kotaro
authors.initials: K
authors.lastname: Shimada
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nakamoto
authors.forename: Kaori
authors.initials: K
authors.lastname: Togashi
mesh_terms: D000328:Adult; D000465:Algorithms; D001659:Biliary Tract / Q000033:anatomy & histology*; D049448:Cholangiopancreatography, Magnetic Resonance / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D018401:Sample Size; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted