Comparison of the diagnostic value of double echo steady state sequences with 30°and 90° flig angle for knee articular cartilage damage / 实用放射学杂志

ABSTRACT

Objective To compare the diagnostic accuracy of 3D-DESS sequences with 30°and 90°flip angles for the knee articular cartilage injury (≥Grade 2).Methods Images of 13 patients (2 men,1 1 women,age range 18-68 years)of the knee articular carti-lage injury were obtained with 3D-DESS flip angles of 30°and 90°at 1.5T MR.Two radiologists classified the presence or absence of cartilage damage of ≥Grade 2 as positive (P)or Arthroscopy was used as the gold stand-ard.The agreement rate of MRI diagnosis with the subsequent arthroscopic diagnosis was compared.Diagnostic scoring of cartilage damage was assessed by three categories3 scores = the absolute diagnosis;2 scores = the probably diagnosis;1 scores = could not make a diagnosis.Results The diagnostic results were compared with 3D-DESS images and arthroscopy;The agreement rate on 90° flip angle was significantly higher than that on 30°flip angle(Kappa value=1.000,0.843,1.000,0.806,0.967,0 .9 0 9 ;P < 0 .0 0 1 , P <0.004,P <0.004,P <0.002,P <0.001,P <0.001),respectively.Images on 90°flip angle were significantly better than that on 30°flip angle to display all the six cartilage surfaces.Conclusion Evaluating knee articular cartilage injury with 3D-DESS sequences, the 90°flip angle is more effective than that on conventional setting of 30°.