title: Prestructural cartilage assessment using MRI.
abstract: Cartilage loss is irreversible, and to date, no effective pharmacotherapies are available to protect or regenerate cartilage. Quantitative prestructural/compositional MR imaging techniques have been developed to characterize the cartilage matrix quality at a stage where abnormal findings are early and potentially reversible, allowing intervention to halt disease progression. The goal of this article is to critically review currently available technologies, present the basic concept behind these techniques, but also to investigate their suitability as imaging biomarkers including their validity, reproducibility, risk prediction and monitoring of therapy. Moreover, we highlighted important clinical applications. This review article focuses on the currently most relevant and clinically applicable technologies, such as T2 mapping, T2*, T1ρ, delayed gadolinium enhanced MRI of cartilage (dGEMRIC), sodium imaging and glycosaminoglycan chemical exchange saturation transfer (gagCEST). To date, most information is available for T2 and T1ρ mapping. dGEMRIC has also been used in multiple clinical studies, although it requires Gd contrast administration. Sodium imaging and gagCEST are promising technologies but are dependent on high field strength and sophisticated software and hardware.
  
  
  
  5 J. Magn. Reson. Imaging 2017;45:949-965.
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California at San Francisco, San Francisco, California, USA.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Link
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California at San Francisco, San Francisco, California, USA.
authors.forename: Jan
authors.initials: J
authors.lastname: Neumann
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California at San Francisco, San Francisco, California, USA.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Li
mesh_terms: D002357:Cartilage Diseases / Q000000981:diagnostic imaging*; D002358:Cartilage, Articular / Q000000981:diagnostic imaging*; D006621:Hip Joint / Q000000981:diagnostic imaging*; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015203:Reproducibility of Results; D012785:Shoulder Joint / Q000000981:diagnostic imaging*
keywords: T1rho; T2 mapping; cartilage; dGEMRIC; quantitative MRI; sodium MRI