title: Bicomponent ultrashort echo time T2* analysis for assessment of patients with patellar tendinopathy.
abstract: To compare bicomponent ultrashort echo time (UTE) T2* parameters of patellar tendon between healthy volunteers and patients with patellar tendinopathy.
  
  
  
  This study was performed with Institutional Review Board approval and with all subjects signing informed consent. A UTE- T2* mapping sequence was performed at 3.0T on the knees of 10 healthy volunteers and in 11 patients with patellar tendinopathy. The UTE- T2* relaxation times of the fast relaxing macromolecular bound water component ( T2*F) and the slow relaxing bulk water component ( T2*S) and the fraction of the fast relaxing macromolecular bound water component (FF) of patellar tendon were measured in all subjects. Wilcoxon rank-sum tests were used to compare UTE- T2* parameters between healthy volunteers and patients with patellar tendinopathy.
  
  
  
  Mean T2*F, T2*S, and FFof the patellar tendon was 1.5 msec, 23.1 msec, and 79.5%, respectively, for healthy volunteers and 1.9 msec, 22.3 msec, and 75.5%, respectively, for patients with patellar tendinopathy. There were statistically significant differences between groups of subjects for T2*F (P = 0.01) and FF(P = 0.007) but not T2*S (P = 0.10) of the patellar tendon.
  
  
  
  Patients with patellar tendinopathy had significantly higher T2*F and significantly lower FFof patellar tendon than healthy volunteers, which suggests that bicomponent UTE- T2* parameters can detect changes in the composition and microstructure of degenerative tendon.
  
  
  
  1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1441-1447.
authors.affiliation: Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Kijowski
authors.affiliation: Department of Orthopedics and Rehabilitation, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
authors.forename: John J
authors.initials: JJ
authors.lastname: Wilson
authors.affiliation: Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
authors.forename: Fang
authors.identifier: 0000-0001-8032-6681
authors.initials: F
authors.lastname: Liu
mesh_terms: D000328:Adult; D002358:Cartilage, Articular; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010329:Patella / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015203:Reproducibility of Results; D052256:Tendinopathy / Q000000981:diagnostic imaging* / Q000503:physiopathology; D055815:Young Adult
keywords: T2 relaxation time; bicomponent; patella; tendon; ultrashort echo time