title: Volumetric multislice gagCEST imaging of articular cartilage: Optimization and comparison with T1rho.
abstract: To develop and optimize a multislice glycosaminoglycan (GAG) chemical exchange saturation transfer (GagCEST) sequence for volumetric imaging of articular cartilage, and to validate the sequence against T1ρrelaxation times in whole joint imaging of tibiotalar cartilage.
  
  
  
  Ex vivo experiments were used to observe the effect of the number of partitions and shot TR on signal-to-noise ratio and measured GagCESTasym. GagCEST imaging of the entire tibiotalar joint was also performed on 10 healthy subjects. The measured GagCESTasymwas compared and correlated with T1ρrelaxation times.
  
  
  
  Ex vivo studies showed a higher average GagCESTasymfrom articular cartilage on multislice acquisitions acquired with two or more partitions than observed with a single-slice acquisition. In healthy human subjects, an average GagCESTasymof 8.8 ± 0.7% was observed. A coefficient of variation of GagCESTasymacross slices of less than 15% was seen for all subjects. Across subjects, a Pearson correlation coefficient of -0.58 was observed between the measured gagCESTasymand T1ρrelaxation times.
  
  
  
  We demonstrated the feasibility and optimization of multislice GagCEST mapping of articular cartilage. Volumetric analysis and decreased scan times will help to advance the clinical utility of GagCEST imaging of articular cartilage. Magn Reson Med 77:1134-1141, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
authors.affiliation: Department of Radiology, Stanford University, Stanford, California, USA.
authors.forename: Feliks
authors.initials: F
authors.lastname: Kogan
authors.affiliation: Department of Radiology, Stanford University, Stanford, California, USA.|Department of Bioengineering, Stanford University, Stanford, California, USA.|Department of Electrical Engineering, Stanford University, Stanford, California, USA.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Hargreaves
authors.affiliation: Department of Radiology, Stanford University, Stanford, California, USA.|Department of Bioengineering, Stanford University, Stanford, California, USA.|Department of Orthopedic Surgery, Stanford University, Stanford, California, USA.
authors.forename: Garry E
authors.initials: GE
authors.lastname: Gold
mesh_terms: D000465:Algorithms; D000818:Animals; D000843:Ankle Joint / Q000033:anatomy & histology / Q000378:metabolism; D002358:Cartilage, Articular / Q000033:anatomy & histology / Q000378:metabolism*; D002417:Cattle; D006025:Glycosaminoglycans / Q000378:metabolism*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D066298:In Vitro Techniques; D008279:Magnetic Resonance Imaging / Q000379:methods*; D057054:Molecular Imaging / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D014018:Tissue Distribution
chemical_list: D006025:Glycosaminoglycans
keywords: GAG; GagCEST; cartilage; osteoarthritis