title: Ultrashort Echo Time T1ρ Is Sensitive to Enzymatic Degeneration of Human Menisci.
abstract: OBJECTIVE
  The aim of the study was to determine whether quantitative ultrashort echo time (UTE) -T1ρ magnetic resonance (MR) measurements are sensitive to proteoglycan degradation in human menisci by trypsin digestion.
  
  
  METHODS
  Conventional and quantitative UTE-T1ρ MR sequences were performed on 4 meniscal samples using a 3T scanner. Magnetic resonance imaging was performed before and after 4, 8, and 12 hours of trypsin solution immersion, inducing proteoglycan loss. One sample was used as a control. Digest solutions were analyzed for glycosaminoglycan (GAG) content. The UTE-T1ρ studies were analyzed for quantitative changes.
  
  
  RESULTS
  Images showed progressive tissue swelling, fiber disorganization, and increase in signal intensity after GAG depletion. The UTE-T1ρ values tended to increase with time after trypsin treatment (P = 0.06). Cumulative GAG loss into the bath showed a trend of increased values for trypsin-treated samples (P = 0.1).
  
  
  CONCLUSIONS
  Ultrashort echo time T1ρ measurements can noninvasively detect and quantify severity of meniscal degeneration, which has been correlated with progression of osteoarthritis.
authors.affiliation: From the *Department of Radiology, VA San Diego Healthcare System; and †Department of Radiology, University of California, San Diego Medical Center, San Diego, CA.
authors.forename: Eric Y
authors.initials: EY
authors.lastname: Chang
authors.forename: Juliana C
authors.initials: JC
authors.lastname: Campos
authors.forename: Won C
authors.initials: WC
authors.lastname: Bae
authors.forename: Richard
authors.initials: R
authors.lastname: Znamirowski
authors.forename: Sheronda
authors.initials: S
authors.lastname: Statum
authors.forename: Jiang
authors.initials: J
authors.lastname: Du
authors.forename: Christine B
authors.initials: CB
authors.lastname: Chung
mesh_terms: D002102:Cadaver; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008592:Menisci, Tibial / Q000473:pathology*; D011509:Proteoglycans / Q000032:analysis*; D015203:Reproducibility of Results
chemical_list: D011509:Proteoglycans