title: Liver fibrosis: Review of current imaging and MRI quantification techniques.
abstract: Liver fibrosis is characterized by the accumulation of extracellular matrix proteins such as collagen in the liver interstitial space. All causes of chronic liver disease may lead to fibrosis and cirrhosis. The severity of liver fibrosis influences the decision to treat or the need to monitor hepatic or extrahepatic complications. The traditional reference standard for diagnosis of liver fibrosis is liver biopsy. However, this technique is invasive, associated with a risk of sampling error, and has low patient acceptance. Imaging techniques offer the potential for noninvasive diagnosis, staging, and monitoring of liver fibrosis. Recently, several of these have been implemented on ultrasound (US), computed tomography, or magnetic resonance imaging (MRI). Techniques that assess changes in liver morphology, texture, or perfusion that accompany liver fibrosis have been implemented on all three imaging modalities. Elastography, which measures changes in mechanical properties associated with liver fibrosis-such as strain, stiffness, or viscoelasticity-is available on US and MRI. Some techniques assessing liver shear stiffness have been adopted clinically, whereas others assessing strain or viscoelasticity remain investigational. Further, some techniques are only available on MRI-such as spin-lattice relaxation time in the rotating frame (T1ρ), diffusion of water molecules, and hepatocellular function based on the uptake of a liver-specific contrast agent-remain investigational in the setting of liver fibrosis staging. In this review, we summarize the key concepts, advantages and limitations, and diagnostic performance of each technique. The use of multiparametric MRI techniques offers the potential for comprehensive assessment of chronic liver disease severity.
  
  
  
  5 J. MAGN. RESON. IMAGING 2017;45:1276-1295.
authors.affiliation: Department of Radiology, Radio-Oncology and Nuclear Medicine, Université de Montréal, Montreal, Quebec, Canada.|Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada.
authors.forename: Léonie
authors.initials: L
authors.lastname: Petitclerc
authors.affiliation: Department of Gastroenterology and Hepatology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Giada
authors.initials: G
authors.lastname: Sebastiani
authors.affiliation: Department of Radiology, Radio-Oncology and Nuclear Medicine, Université de Montréal, Montreal, Quebec, Canada.|MR Clinical Science, Philips Healthcare Canada, Markham, Ontario, Canada.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Gilbert
authors.affiliation: Department of Radiology, Radio-Oncology and Nuclear Medicine, Université de Montréal, Montreal, Quebec, Canada.|Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada.|Institute of Biomedical Engineering, Université de Montréal, CP 6128, Succursale Centre-ville, Montréal, Québec, Canada.|Laboratory of Biorheology and Medical Ultrasonics, CRCHUM, 900 Saint-Denis, Montréal, Québec, Canada.
authors.forename: Guy
authors.initials: G
authors.lastname: Cloutier
authors.affiliation: Department of Radiology, Radio-Oncology and Nuclear Medicine, Université de Montréal, Montreal, Quebec, Canada.|Centre de recherche du Centre hospitalier de l'Université de Montréal (CRCHUM), Montreal, Quebec, Canada.|Institute of Biomedical Engineering, Université de Montréal, CP 6128, Succursale Centre-ville, Montréal, Québec, Canada.
authors.forename: An
authors.initials: A
authors.lastname: Tang
mesh_terms: D001706:Biopsy; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D004548:Elasticity; D054459:Elasticity Imaging Techniques / Q000379:methods*; D006801:Humans; D008099:Liver / Q000473:pathology; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging* / Q000473:pathology; D008107:Liver Diseases / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D010477:Perfusion; D014783:Viscosity
chemical_list: D003287:Contrast Media
keywords: elastography; liver fibrosis; magnetic resonance; review article; ultrasound; viscoelasticity