EVALUATION OF PATELLAR CARTILAGE SURFACE LESIONS - COMPARISON OF CT ARTHROGRAPHY AND FAT-SUPPRESSED FLASH 3D MR-IMAGING

The aim of this study was to evaluate the sensitivity and specificity of fat-suppressed fast low-angle shot (FLASH) 3D MR imaging in the det ection of patellar cartilage surface lesions in comparison with CT art hrography. Fifty patients, with or without symptoms of chondromalacia, were prospectively examined by CT arthrography and fat-suppressed 3D gradient-echo MR imaging. All MR examinations,;,were evaluated by thre e observers, two of them reaching a consensus interpretation. The lesi ons were graded according to their morphology and their extent. The CT arthrography was considered as the reference examination. For both se ts of observers, the final diagnosis of chondromalacia was obtained il l 92.5 %. The specificity was 60 % on a patient-by-patient basis. Fiss ures were missed in 83 and 60 %, respectively, but were isolated findi ngs only in 2.5 % of the cases. Considering ulcers involving more than 50 % of the cartilage thickness, 65 and 88 %, respectively, were reco gnized. Fat-suppressed FLASH 3D is an adequate pulse sequence for the detection of pa,tellar cartilage ulcers. It can be applied on a routin e clinical basis, but it does not show as many fissures as CT arthrogr aphy and is less precise for grading of lesions.