膝关节单纯软骨损伤的MR成像

MRI Findings of Pure Cartilage Injury of the Knee Joint

目的 探讨膝关节单纯软骨损伤MRI表现并讨论其损伤机制、成像方法。资料与方法 搜集16例平片阴性的膝部疼痛患者的MRH资料,分别采用平面回波成像(EPI)和梯度回波(GRE)序列成像,矢状位为常规观察断面,横断面作为补充。结果 16例24处软骨出现形态或内部信号异常,包括软骨表面锯齿状凹陷、波浪状缺损、压缩变扁。信号异常在EPI上表现为条状低信号,GRE上略呈高信号。结论 膝关节单纯软骨损伤MRI依损伤程度可分软骨表面正常但信号有异常、软骨表面不同程度缺损、全软骨压缩或缺损3种改变,MRI是软骨损害最佳无创检查方法。

Objective To analyze MRI manifestations of pure cartilage injury of the knee joint, and to discuss the key points of imaging technique and the mechanism of injury. Materials and Methods Using EPI and GRE sequences, sagittal and axial MRI scanning was performed in 16 patients with painful knee joint and normal plain radiograph of knee joint. MRI signs were observed and analyzed. Results A total 24 morphologic or signal abnormalities were found in 16 cases, which included serrated surface of the cartilage, undulated defect of the cartilage or compressed cartilage. Abnormal stripe low-signal on EPI and slight high-signal on GRE were demonstrated. Conclusion Based on the injury severity, pure cartilage injury of the knee joint can be divided into three patterns: (1) abnormal signal with normal cartilage surface; (2) defect of cartilage surface in different degree; (3) totally compressed or destructed of the cartilage. MRI is the best non-invasive method for studying cartilage injury.