title: Accuracy and precision of quantitative assessment of cartilage morphology by magnetic resonance imaging at 3.0T.
abstract: OBJECTIVE
  Quantitative magnetic resonance imaging (MRI) of articular cartilage represents a powerful tool in osteoarthritis (OA) research, but has so far been confined to a field strength of 1.5T. The aim of this study was to evaluate the precision of quantitative MRI assessments of human cartilage morphology at 3.0T and to correlate the measurements at 3.0T with validated measurements at 1.5T.
  
  
  METHODS
  MR images of the knee of 15 participants with OA and 15 healthy control subjects were acquired using Siemens 1.5T and 3.0T scanners. Double oblique coronal scans were obtained at 1.5T with a 1.5-mm partition thickness, at 3.0T with a 1.5-mm partition thickness, and at 3.0T with a 1.0-mm partition thickness. Cartilage volume, thickness, and surface area of the femorotibial cartilage plates were quantified using proprietary software.
  
  
  RESULTS
  For 1.5-mm partition thickness at 1.5T, the precision error was 3.0% and 2.6% for cartilage volume and cartilage thickness, respectively. The error was smaller for a 1.5-mm partition thickness at 3.0T (2.6% and 2.5%) and still smaller for a 1.0-mm partition thickness at 3.0T (2.1% and 2.0%). Correlation coefficients between values obtained at 3.0T and 1.5T were high (r > or = 0.96), with no significant deviation between the two field strengths.
  
  
  CONCLUSIONS
  Quantitative MRI measurement of cartilage morphology at 3.0T (partition thickness 1 mm) was found to be accurate and tended to be more reproducible than at 1.5T (partition thickness 1.5 mm). Imaging at 3.0T may therefore provide superior ability to detect changes in cartilage status over time and to determine responses to treatment with structure-modifying drugs.
authors.affiliation: Paracelsus Private Medical University, Salzburg, Austria. felix.Eckstein@pmu.ac.at
authors.forename: Felix
authors.initials: F
authors.lastname: Eckstein
authors.forename: H Cecil
authors.initials: HC
authors.lastname: Charles
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Buck
authors.forename: Virginia B
authors.initials: VB
authors.lastname: Kraus
authors.forename: Ann E
authors.initials: AE
authors.lastname: Remmers
authors.forename: Martin
authors.initials: M
authors.lastname: Hudelmaier
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wirth
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Evelhoch
mesh_terms: D000368:Aged; D002356:Cartilage / Q000473:pathology*; D005260:Female; D005269:Femur; D006801:Humans; D007719:Knee Joint / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards*; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000473:pathology*; D015203:Reproducibility of Results; D013977:Tibia