title: [MR imaging of the Achilles tendon: evaluation of criteria for the differentiation of asymptomatic and symptomatic tendons].
abstract: OBJECTIVE
  The purpose of this study was to develop quantitative and qualitative MRI criteria to differentiate between healthy and pathological Achilles tendons.
  
  
  METHODS
  364 Achilles tendons were examined on a 1.5 T MRI scanner. 264 patients had Achilles tendon complaints, 100 asymptomatic Achilles tendons served as a control. T 1-weighted, T 2-weighted and a STIR sequence were performed in sagittal and axial orientation. Images were evaluated in consensus by two radiologists. Quantitative and qualitative criteria were assessed. A Mann-Whitney-U-Test and a regression analysis were used for statistical analysis.
  
  
  RESULTS
  There were statistically significant differences between the patients with disorders and the control group concerning the depth (12.0 mm and 6.3 mm, p < 0.001) and length (83.2 mm and 45.9 mm, p < 0.001) of the tendon, the area of the tendon cross section (1.60 mm (2) and 061 mm (2), p < 0.001), as well as the length of the bursa retrocalcanea (8.3 mm and 5.3 mm, p < 0.001). There was a sensitivity of 97 % and a specificity of 91 % using a formula including the 3 criteria: tendon depth (A4), length of bursa (A5) and area of tendon (F).
  
  
  CONCLUSIONS
  The measurement of the Achilles tendon and the binary-logistic regression analysis allow differentiation between normal and pathological Achilles tendons.
authors.affiliation: Klinik und Poliklinik für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Hamburg-Eppendorf, Hamburg.
authors.forename: C
authors.initials: C
authors.lastname: Weber
authors.forename: U
authors.initials: U
authors.lastname: Wedegärtner
authors.forename: L C
authors.initials: LC
authors.lastname: Maas
authors.forename: R
authors.initials: R
authors.lastname: Buchert
authors.forename: G
authors.initials: G
authors.lastname: Adam
authors.forename: R
authors.initials: R
authors.lastname: Maas
mesh_terms: D000125:Achilles Tendon / Q000293:injuries* / Q000473:pathology*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012421:Rupture; D012680:Sensitivity and Specificity; D052256:Tendinopathy / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D055815:Young Adult