title: A preliminary study of the T1rho values of normal knee cartilage using 3T-MRI.
abstract: BACKGROUND
  To investigate the degree of the effect of aging and weight-bearing on T1rho values in normal cartilage.
  
  
  METHODS
  Thirty-two asymptomatic patients were examined using 3.0-T magnetic resonance imaging (MRI) to determine knee cartilage T1rho values and T2 values. The femoral and tibial cartilage was divided into weight-bearing (WB-Rs) and less-weight-bearing (LWB-Rs) regions. Single regression analysis was used to assess the relationship between cartilage T1rho values and age and between T2 values and age. Analysis of variance and post hoc-testing were used to evaluate differences in WB-Rs and LWB-Rs cartilage T1rho values and T2 values. Multiple linear regression modeling was performed to predict cartilage T1rho values.
  
  
  RESULTS
  Cartilage T1rho values correlated positively with age for all cartilage regions tested (p<0.001). There were no significant correlations between cartilage T2 values and age. In both the medial femoral and tibial cartilage, T1rho values were significantly higher in WB-Rs than in LWB-Rs (p<0.05). There were no significant differences in T2 values between WB-Rs and LWB-Rs. Multiple linear regression analysis showed that both age and weight-bearing were significant predictors of increased medial knee cartilage T1rho values (p<0.001).
  
  
  CONCLUSIONS
  Aging and the degree of weight-bearing correlate with the change in cartilage T1rho values. Based on multiple regression modeling, aging may be a more important factor than weight-bearing for cartilage T1rho values.
authors.affiliation: Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan. hjmgoto@hotmail.co.jp
authors.forename: Hajimu
authors.initials: H
authors.lastname: Goto
authors.forename: Yuki
authors.initials: Y
authors.lastname: Iwama
authors.forename: Masahiko
authors.initials: M
authors.lastname: Fujii
authors.forename: Nobukazu
authors.initials: N
authors.lastname: Aoyama
authors.forename: Seiji
authors.initials: S
authors.lastname: Kubo
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Kuroda
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Ohno
authors.forename: Kazuro
authors.initials: K
authors.lastname: Sugimura
mesh_terms: D000328:Adult; D000465:Algorithms; D000704:Analysis of Variance; D002358:Cartilage, Articular / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012044:Regression Analysis; D016474:Weight-Bearing