title: MRI-based staging of hepatic fibrosis: Comparison of intravoxel incoherent motion diffusion-weighted imaging with magnetic resonance elastography.
abstract: OBJECTIVE
  To evaluate the use of intravoxel incoherent motion (IVIM) imaging for staging hepatic fibrosis, and compare its staging ability with that of magnetic resonance elastography (MRE).
  
  
  METHODS
  This study included 129 patients with pathologically staged liver fibrosis, and 53 patients with healthy livers. All patients underwent both MRE and IVIM imaging. Four diffusivity indices were calculated with 11 b-values; slow diffusion coefficient related to molecular diffusion (D), fast diffusion coefficient related to perfusion in micro-vessels (D*), perfusion-related diffusion fraction (f), and apparent diffusion coefficient (ADC). Receiver operating characteristic curve analysis was performed to determine the accuracy of IVIM imaging and MRE for staging hepatic fibrosis.
  
  
  RESULTS
  D*, f, and ADC values decreased significantly with fibrosis stage (P < 0.0124), and liver stiffness increased (P < 0.0001). The Az value of MRE was significantly higher than that of D* for all fibrosis stages (D* vs. MRE for ≥ F1, 0.851 vs. 0.992 [P < 0.0001]; ≥ F2, 0.898 vs. 0.998 [P = 0.0003]; ≥ F3, 0.904 vs. 0.995 [P = 0.0004]; F4, 0.885 vs. 0.996 [P < 0.0001]).
  
  
  CONCLUSIONS
  IVIM imaging is a useful technique for evaluating hepatic fibrosis, but MRE is better able to discriminate fibrosis stages than IVIM imaging.
authors.affiliation: Department of Radiology, University of Yamanashi, Yamanashi, Japan.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Ichikawa
authors.affiliation: Department of Radiology, University of Yamanashi, Yamanashi, Japan.
authors.forename: Utaroh
authors.initials: U
authors.lastname: Motosugi
authors.affiliation: Department of Radiology, University of Yamanashi, Yamanashi, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Morisaka
authors.affiliation: Department of Radiology, University of Yamanashi, Yamanashi, Japan.
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Sano
authors.affiliation: Department of Radiology, University of Yamanashi, Yamanashi, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Ichikawa
authors.affiliation: First Department of Internal Medicine, University of Yamanashi, Yamanashi, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Enomoto
authors.affiliation: First Department of Surgery, University of Yamanashi, Yamanashi, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Matsuda
authors.affiliation: First Department of Surgery, University of Yamanashi, Yamanashi, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Fujii
authors.affiliation: Department of Radiology, University of Yamanashi, Yamanashi, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Onishi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004058:Diffusion; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008103:Liver Cirrhosis / Q000473:pathology* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009038:Motion; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
keywords: diffusion-weighted imaging (DWI); hepatic fibrosis; intravoxel incoherent motion (IVIM); magnetic resonance elastography (MRE); magnetic resonance imaging (MRI)