title: Patellar articular cartilage lesions: in vitro MR imaging evaluation after placement in gadopentetate dimeglumine solution.
abstract: OBJECTIVE
  To evaluate T1-weighted magnetic resonance (MR) imaging after diffusion of gadopentetate dimeglumine for visualization of articular cartilage lesions.
  
  
  METHODS
  MR imaging was performed in eight human cadaveric patella specimens immediately and 4 hours after placement into a vessel filled with gadopentetate dimeglumine solution (2.5 mmol/L). T1-weighted spin-echo and inversion-recovery turbo spin-echo MR sequences with nulled cartilage signal (inversion time of 300 msec) were used. In a total of 128 articular cartilage areas, MR imaging findings were compared with macroscopic and histopathologic findings. Pathologic evaluation was performed by one musculoskeletal pathologist. With knowledge of pathologic observations, MR images were analyzed by one musculoskeletal radiologist with regard to intrinsic signal intensity characteristics and surface abnormalities of articular cartilage.
  
  
  RESULTS
  Histopathologic findings demonstrated 67 areas of normal articular cartilage and 66 cartilage lesions (grade 1, n = 19; grade 2, n = 15; grade 3, n = 26; grade 4, n = 6). All grade 3 and 4 lesions could be identified on MR images obtained immediately after submersion and after 4 hours. Ninety-four percent of grade 1 and 2 lesions were identified as areas of predominantly decreased contrast enhancement on delayed MR images obtained with both sequences. MR images obtained immediately after submersion demonstrated abnormal signal intensity in only 9% and 12% of grade 1 and 2 lesions, respectively.
  
  
  CONCLUSIONS
  T1-weighted MR images obtained in vitro after gadopentetate dimeglumine diffusion allow demonstration of articular cartilage surface lesions and early stages of cartilage degradation.
authors.affiliation: Department of Radiology, Technische Universitaet Muenchen, Ismaninger Str 22, D-81675 Munich, Germany. woertler@roe.med.tu-muenchen.de
authors.forename: Klaus
authors.initials: K
authors.lastname: Woertler
authors.forename: Horst
authors.initials: H
authors.lastname: Buerger
authors.forename: Jens
authors.initials: J
authors.lastname: Moeller
authors.forename: Ernst J
authors.initials: EJ
authors.lastname: Rummeny
mesh_terms: D000368:Aged; D002358:Cartilage, Articular / Q000293:injuries* / Q000473:pathology; D003287:Contrast Media / Q000008:administration & dosage* / Q000493:pharmacokinetics; D004058:Diffusion; D019786:Gadolinium DTPA / Q000493:pharmacokinetics; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D010007:Osteochondritis / Q000175:diagnosis / Q000473:pathology; D010329:Patella / Q000293:injuries* / Q000473:pathology; D012680:Sensitivity and Specificity; D013382:Subtraction Technique
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA