title: Magnetic resonance diagnosis of the anterior labrum and capsule. Effect of field strength on efficacy.
abstract: OBJECTIVE
  The authors compare the performance of high-field and low-field magnetic resonance (MR) systems in the evaluation of shoulder instability, 35 patients were examined at field strengths of 1.0 T and of 0.2 T.
  
  
  METHODS
  Surface coils were used in both systems. Because arthroscopy was used as gold standard, a preselected patient-population was obtained for the study.
  
  
  RESULTS
  The sensitivity/specificity/accuracy of MR images acquired at 1.0 T for labrum pathology were 91%/67%/91% and 70%/80%/71% for the capsular complex. Compared with the above, the sensitivity/specificity/accuracy for 0.2 T MR images revealed 91%/67%/91% for the labrum pathology and 63%/80%/66% for the capsular complex respectively. In the evaluation of capsular lesions a comparison between the 0.2 T MR system and the 1.0 T system indicated a higher sensitivity and accuracy for the high-field images. Concerning labral lesions, the sensitivity and accuracy of the 0.2 T MR imager and the 1.0 T imager were comparable.
  
  
  CONCLUSIONS
  Given differences in imaging protocols, imaging at 0.2 T does not adversely affect the assessment of shoulder instability when compared with imaging at 1.0 T. These preliminary results warrant more extensive clinical comparison of results obtained at different magnetic field strengths.
authors.affiliation: Department of Diagnostic Radiology, Freiburg University Hospital, Germany. Kha@mrs1.ukl.uni-freiburg.de
authors.forename: K H
authors.initials: KH
authors.lastname: Allmann
authors.forename: O
authors.initials: O
authors.lastname: Walter
authors.forename: J
authors.initials: J
authors.lastname: Laubenberger
authors.forename: M
authors.initials: M
authors.lastname: Uhl
authors.forename: C H
authors.initials: CH
authors.lastname: Buitrago-Tellez
authors.forename: N
authors.initials: N
authors.lastname: Biebow
authors.forename: M
authors.initials: M
authors.lastname: Langer
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D012783:Shoulder Dislocation / Q000175:diagnosis*; D012785:Shoulder Joint