title: Rapid multicomponent T2 analysis of the articular cartilage of the human knee joint at 3.0T.
abstract: OBJECTIVE
  To determine the feasibility of using multicomponent-driven equilibrium single-shot observation of T1 and T2 (mcDESPOT) for evaluating the human knee joint at 3.0T and to investigate depth-dependent and regional-dependent variations in multicomponent T2 parameters within articular cartilage.
  
  
  METHODS
  mcDESPOT was performed on the knee joint of 10 asymptomatic volunteers at 3.0T. Single-component T2 relaxation time (T2single ), multicomponent T2 relaxation time for water tightly bound to proteoglycan (T2PG ) and bulk water loosely bound to the macromolecular matrix (T2BW ), and fraction of water tightly bound to proteoglycan (FPG ) were measured in eight cartilage subsections and within the superficial and deep layers of patellar cartilage. Statistical analysis was used to investigate depth-dependent and regional-dependent variations in parameters.
  
  
  RESULTS
  There was lower (P = 0.001) T2single and T2PG and higher (P < 0.001) FPG in the deep than superficial layer of patellar cartilage. There was higher (P < 0.001) FPG on the weight-bearing surfaces than nonweight-bearing surfaces. There was higher (P < 0.001) T2single , T2PG , and T2BW on the trochlea and posterior medial and lateral femoral condyles than the patella, central medial and lateral femoral condyles, and medial and lateral tibia plateaus.
  
  
  CONCLUSIONS
  Multicomponent T2 parameters of the articular cartilage of the human knee joint can be measured at 3.0T using mcDESPOT and show depth-dependent and regional-dependent variations.
authors.affiliation: Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.forename: Rajeev
authors.initials: R
authors.lastname: Chaudhary
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Hurley
authors.forename: Alejandro
authors.initials: A
authors.lastname: Munoz Del Rio
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Alexander
authors.forename: Alexey
authors.initials: A
authors.lastname: Samsonov
authors.forename: Walter F
authors.initials: WF
authors.lastname: Block
authors.forename: Richard
authors.initials: R
authors.lastname: Kijowski
mesh_terms: D000328:Adult; D000465:Algorithms; D002358:Cartilage, Articular / Q000033:anatomy & histology*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007719:Knee Joint / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015588:Observer Variation; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
keywords: T2 relaxation time; cartilage; knee; multicomponent; relaxometry