The study of selective water excitation in the MR imaging of articular cartilage / 中华放射学杂志

ABSTRACT

Objective To investigate the value of selective water excitation technique for the assessment of articular cartilage.Methods MR sagittal scanning of knee joints was performed in the fifteen healthy volunteers.MR scan sequences were 3D-FFE-SPIR and 3D-FFE-WATS.The signal noise ratio (SNR)of the cartilage,the contrast noise ratio(CNR)between cartilage and adjacent tissue and their efficiency were calculated and analyzed statistically.Tweenty-nine patients who were suspected having cartilage injury were performed MR examination anti the image characteristics and the detecting ability of each sequence on cartilage lesions were analyzed.Results In the healthy volunteers,the cartilage SNR was 3D-FFE-SPIR:197.93?18.58,3D-FFE-WATS:187.32?21.50(P=0.159).CNR(cartilage/bone)was 3D-FFE-SPIR:185.50?18.34,3D-FFE-WATS:169.55?24.57(P=0.054).CNR(cartilage/muscle)was 3D-FFE-SPIR:61.40?19.04,3D-FFE-WATS:47.27?21.05(P=0.064).The cartilage SNR and CNR between cartilage and bone,muscle of 3D-FFE-SPIR weren't significantly higher than that of 3D-FFE- WATS.CNR(cartilage/liquid)was 3D-FFE-SPIR:91.53?14.46,3D-FFE-WATS:149.28?32.30(P= 0.000).CNR(cartilage/marrow)was 3D-FFE-SPIR:159.26?18.83,3D-FFE-WATS:176.87? 22.50(P=0.028).CNR(cartilage/fat)was 3 D-FFE-SPIR:134.56?15.80,3D-FFE-WATS:154.01? 22.42(P =0.010).The CNR between cartilage and liquid,marrow,fat were higher in 3D-FFE-WATS and significantly different than that of 3D-FFE-SPIR.Thirty detected cartilage injuries of patients were 3D-FFE- WATS:39,3D-FFE-SPIR:45 and there was no statistical difference between them(P=0.37). Conclusion 3D-FFE-WATS can show the articular cartilage clearly.It has high scan speed and suppress the fat signal evenly.Its ability for finding cartilage damage is equal to that of 3D-FFE-SPIR.So WATS can be used in the routine clinical cartilage examination.