To compare signal-to-noise ratios (S/N) and contrast-to-noise ratios (C/N) in various MR sequences, including fat-suppressed three-dimensional spoiled gradient-echo (SPGR) imaging, fat-suppressed fast spin echo (FSE) imaging, and fat-suppressed three-dimensional driven equilibrium Fourier transform (DEFT) imaging, and to determine the diagnostic accuracy of these imaging sequences for detecting cartilage lesions in osteoarthritic knees, as compared with arthroscopy.Two sagittal fat-suppressed FSE images (repetition time [TR] / echo time [TE], 4000/13 [FSE short TE] and 4000/39 [FSE long TE]), sagittal fat-suppressed three-dimensional SPGR images (60/5, 40 degrees flip angle), and sagittal fat-suppressed echo-planar three-dimensional DEFT images (400/21.2) were acquired in 35 knees from 28 patients with osteoarthritis of the knee. The S/N efficiencies (S/Neffs) of cartilage, synovial fluid, muscle, meniscus, bone marrow, and fat tissue, and the C/N efficiencies (C/Neffs) of these structures were calculated. Kappa values, exact agreement, sensitivity, specificity, positive predictive value, and negative predictive value were determined by comparison of MR grading with arthroscopic results.The synovial fluid S/Neff on fat-suppressed FSE short TE images, fat-suppressed FSE long TE images, and fat-suppressed three-dimensional DEFT images showed similar values. Fat-suppressed three-dimensional DEFT images showed the highest fluid-cartilage C/Neff of all sequences. All images showed fair to good agreement with arthroscopy (kappa, 0.615 in FSE short TE, 0.601 in FSE long TE, 0.583 in three-dimensional SPGR, and 0.561 in three-dimensional DEFT). Although the sensitivity of all sequences was high (100% in FSE short TE, FSE long TE, and DEFT; 96.7% in SPGR), specificity was relatively low (67.6% in FSE short TE and FSE long TE; 85.3% in SPGR; 58.3% in DEFT). The peripheral area of bone marrow edema or whole area of bone marrow edema on fat-suppressed FSE images was demonstrated as low or iso-signal intensity on fat-suppressed three-dimensional DEFT images.Fat-suppressed three-dimensional SPGR imaging and fat-suppressed FSE imaging showed high sensitivity and high negative predictive values, but relatively low specificity. The Kappa value and exact agreement was the highest on fat-suppressed FSE short TE images. Fat-suppressed three-dimensional DEFT images showed results similar to the conventional sequences.
View details for DOI 10.1002/jmri.20193
View details for Web of Science ID 000224762700017
View details for PubMedID 15503323