title: MRI-derived T2 relaxation times and cartilage morphometry of the tibio-femoral joint in subjects with and without osteoarthritis during a 1-year follow-up.
abstract: OBJECTIVE
  To assess differences in magnetic resonance imaging (MRI)-based compositional (T2) and morphometric (volume and thickness) parameters of the tibio-femoral joint cartilage in subjects with and without osteoarthritis (OA) and compare these with clinical assessment tools during a 1-year follow-up.
  
  
  METHODS
  Three Tesla MRI of the knee joint was performed in eight female patients (body mass index [BMI]>30) with early OA and 10 age-matched female controls (BMI<30) at baseline (BL) and after 3, 6 and 12 months. Cartilage T2 maps, volume and average thickness were calculated in five compartments (medial/lateral femoral condyle, medial/lateral tibia and trochlea). These data were correlated with changes in clinical parameters and joint space width determined in standardized knee radiographs using a mixed random effects model.
  
  
  RESULTS
  At BL, T2 was significantly higher (P<0.05) across the cartilage in patients (45.68+/-5.17ms) compared to controls (41.75+/-4.33ms). Patients had significantly (P<0.05) less cartilage volume and less average cartilage thickness in the tibia than controls (2.10+/-0.53cm(3) vs 2.91+/-0.49cm(3) and 1.59+/-0.24mm vs 1.90+/-0.29mm, respectively). A significant change in clinical parameters of OA, cartilage T2 values or a decrease of volume and average thickness could not be demonstrated within both groups.
  
  
  CONCLUSIONS
  Significant differences between the groups indicate that both T2 and morphometric parameters may be useful in quantifying early OA related changes. In a 12-month follow-up, however, no significant alterations of the studied parameters were found, which may be due to the length of the observation interval.
authors.affiliation: Department of Radiology, University of California, San Francisco, 185 Berry Street, Suite 350, San Francisco, CA 94107-0946, USA. Robert.Stahl@radiology.ucsf.edu
authors.forename: R
authors.initials: R
authors.lastname: Stahl
authors.forename: G
authors.initials: G
authors.lastname: Blumenkrantz
authors.forename: J
authors.initials: J
authors.lastname: Carballido-Gamio
authors.forename: S
authors.initials: S
authors.lastname: Zhao
authors.forename: T
authors.initials: T
authors.lastname: Munoz
authors.forename: M P
authors.initials: MP
authors.lastname: Hellio Le Graverand-Gastineau
authors.forename: X
authors.initials: X
authors.lastname: Li
authors.forename: S
authors.initials: S
authors.lastname: Majumdar
authors.forename: T M
authors.initials: TM
authors.lastname: Link
mesh_terms: D002358:Cartilage, Articular / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement; D007719:Knee Joint / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000175:diagnosis*