中文摘要：

目的以关节镜检查结果为金标准,比较三维抑脂扰相梯度回波（3D-SPGR）序列和三维稳态自由进动成像（3D-SSFP）序列在膝关节软骨病变的诊断准确性。资料与方法对连续54例患者的58个膝关节行矢状位3D-SPGR和3D-SSFP序列扫描。按照改良的Noyes评分标准对膝关节软骨进行MRI和关节镜分级。计算上述MR序列对膝关节软骨病变的诊断敏感性、特异性和准确性。通过K统计评价不同阅片者间结果的一致性。结果3D-SSFP序列对诊断膝关节软骨病变的敏感性、特异性和准确性分别为80%、94%和92%（阅片者1）;76%、94%和90%（阅片者2）。而3D-SPGR序列对诊断膝关节软骨病变的敏感性、特异性和准确性则分别为82%、92%和90%（阅片者1）;82%、90%和88%（阅片者2）。两阅片者阅片结果一致性为良～优（Kappa值为0.43～0.83）。结论3D-SSFP序列在诊断膝关节软骨病变方面与3D-SPGR序列有同等的价值,其较短的图像采集时间更适合作为膝关节的MR扫描常规序列。

英文摘要：

Objective To compare the diagnostic accuracy of three dimensional steady-state free-precession（3D SSFP） sequence and fat-suppressed three-dimensional spoiled gradient-recalled （3D SPGR）in the evaluation of articular cartilage lesions in the knee with arthroscopy results as reference standard.Materials and Methods 58 knees in 54 patients were evaluated by using sagittal 3D SSFP and fat-suppressed 3D SPGR sequences.Cartilage lesions were graded by MRI and arthroscopy,a modified Noyes scoring system was employed. Sensitivity,specificity,and accuracy were assessed. Interobserver agreement was determined with κstatistics.Results The performance of 3D SSFP sequence （sensitivity,specificity and accuracy were 80%,94%,and 92% for reader 1 and 76%,94%,and 90% for reader 2 respectively） was similar to that of fat-suppressed 3D SPGR sequence （sensitivity,specificity and accuracy were 82%,92%,and 90% for reader 1 and 82%,90%,and 88% for reader 2 respectively） in the detection of knee articular cartilage lesions.The interobserver agreement varied from fair to good to excellent（Kappa values from 0.43-0.83）.Conclusion 3D SSFP is a sequence with a well diagnostic performance that is comparable with fat-suppressed 3D SPGR in evaluating the knee cartilage lesions,and it can be integrated with routine knee MRI protocols due to short acquisition time.