title: Improved detection of hypervascular liver lesions with CAIPIRINHA-Dixon-TWIST-volume-interpolated breath-hold examination.
abstract: OBJECTIVE
  The aim of this study was to assess the diagnostic performance of a dynamic, multiphasic contrast-enhanced volume-interpolated sequence with advanced parallel imaging techniques, Dixon fat saturation, and view sharing with 5 hepatic arterial subphases for the detection of focal liver lesions.
  
  
  METHODS
  Twenty-four consecutive patients (13 females, 11 males; mean [SD] age, 58 [15] years) with focal liver lesions were included in this prospective study. The examination was performed at a 3-T magnetic resonance imaging system (MAGNETOM Skyra; Siemens Healthcare, Erlangen, Germany). Five dynamic arterial subphases with a temporal resolution of 2.6 seconds, starting 17 seconds after injection of the hepatobiliary contrast agent gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Eovist; Bayer HealthCare, Leverkusen, Germany), were acquired using an accelerated parallel imaging volume-interpolated sequence with view sharing (multiarterial controlled aliasing in parallel imaging results in higher acceleration-Dixon-time-resolved angiography with interleaved stochastic trajectories-volumetric interpolated breath-hold examination [MA-CDT-VIBE]). The fourth of the 5 arterial acquisition phases (ie, at 24.8 seconds after the start of contrast agent injection) was considered the equivalent of a standard hepatic arterial phase (equivalent standard arterial phase [ESAP]). The diagnostic value of all 5 dynamic arterial phases for the detection of focal liver lesions, as compared with the single ESAP, was judged in 2 independent consensus readings. The 2 consensus reading groups were blinded to each others' results. The complete, comprehensive multisequence magnetic resonance imaging examination, including T1-weighted, T2-weighted, and multiphasic contrast-enhanced sequences, served as the standard of reference for lesion detection.
  
  
  RESULTS
  Forty-six percent of the patients (11/24) had hypervascular lesions. In 79 % of all patients (19/24), the best arterial parenchymal contrast of one of the MA-CDT-VIBE acquisition phases was considered better than that of the ESAP. In one third of all cases (8/24 for the first and 6/24 for the second consensus reading), MA-CDT-VIBE showed an improved lesion detection rate compared with ESAP, especially in hypervascular lesions (4/11, representing 36% of all patients with hypervascular lesions). There was a high degree of interrater agreement between the 2 consensus reading groups (the Cohen κ, 0.71-1.00; P < 0.001).
  
  
  CONCLUSIONS
  Compared with a standard hepatic arterial phase, MA-CDT-VIBE with 5 hepatic arterial subphases demonstrated greater diagnostic accuracy for the detection of hypervascular focal liver lesions and provided a robust and optimized hepatic arterial acquisition phase.
authors.affiliation: From the *Department of Clinical Radiology, University Hospitals Munich, Munich; and †Department of Diagnostic and Interventional Radiology, University Hospital Tuebingen, Tuebingen, Germany.
authors.forename: Philipp M
authors.initials: PM
authors.lastname: Kazmierczak
authors.forename: Daniel
authors.initials: D
authors.lastname: Theisen
authors.forename: Kolja M
authors.initials: KM
authors.lastname: Thierfelder
authors.forename: Wieland H
authors.initials: WH
authors.lastname: Sommer
authors.forename: Maximilian F
authors.initials: MF
authors.lastname: Reiser
authors.forename: Mike
authors.initials: M
authors.lastname: Notohamiprodjo
authors.forename: Konstantin
authors.initials: K
authors.lastname: Nikolaou
mesh_terms: D000465:Algorithms; D062485:Breath Holding; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008113:Liver Neoplasms / Q000098:blood supply / Q000473:pathology*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000473:pathology*; D010363:Pattern Recognition, Automated / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity