title: Cartilage and meniscus assessment using T1rho and T2 measurements in healthy subjects and patients with osteoarthritis.
abstract: OBJECTIVE
  The purpose of this study was to evaluate meniscal degeneration in healthy subjects and subjects with osteoarthritis (OA) using T(1ρ) and T(2) measurements and to examine the interrelationship between cartilage and meniscus abnormalities.
  
  
  METHODS
  Quantitative assessment of cartilage and meniscus was performed using 3T Magnetic Resonance Imaging (MRI) with a T(1ρ) and T(2) mapping technique in 19 controls and 44 OA patients. A sagittal T(2)-weighted fast spin echo (FSE) fat-saturated image was acquired for cartilage and meniscal Whole-Organ Magnetic Resonance Imaging Score (WORMS) assessment. Western Ontario and McMasters Universities Arthritis Index (WOMAC) scores were obtained to assess clinical symptoms.
  
  
  RESULTS
  The posterior horn of the medial meniscus (PHMED) had the highest incidence of degeneration. Stratifying subjects on the basis of PHMED grade revealed that the T(1ρ) and the T(2) measurements of the PHMED and the medial tibial (MT) cartilage were higher in subjects having a meniscal tear (meniscal grade 2-4) compared to subjects with a meniscal grade of 0 or 1 (P<0.05). While not statistically significant, there was a trend for T(1ρ) and T(2) being higher in PHMED grade 1 compared to grade 0 (P=0.094, P=0.073 respectively). WOMAC scores had a stronger correlation with meniscus relaxation measures than cartilage measures.
  
  
  CONCLUSIONS
  Magnetic Resonance (MR) T(1ρ) and T(2) measurements provide a non-invasive means of detecting and quantifying the severity of meniscal degeneration. Meniscal damage has been implicated in OA progression and is correlated with cartilage degeneration. Early detection of meniscal damage represented by elevations in meniscal relaxation measures may identify subjects at increased risk for OA.
authors.affiliation: Musculoskeletal and Quantitative Imaging Research Group, Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA 94158, USA.
authors.forename: Z A
authors.initials: ZA
authors.lastname: Zarins
authors.forename: R I
authors.initials: RI
authors.lastname: Bolbos
authors.forename: J B
authors.initials: JB
authors.lastname: Pialat
authors.forename: T M
authors.initials: TM
authors.lastname: Link
authors.forename: X
authors.initials: X
authors.lastname: Li
authors.forename: R B
authors.initials: RB
authors.lastname: Souza
authors.forename: S
authors.initials: S
authors.lastname: Majumdar
mesh_terms: D000328:Adult; D000368:Aged; D002358:Cartilage, Articular / Q000473:pathology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology*; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000473:pathology*; D000070600:Tibial Meniscus Injuries