多模态MRI诊断早期髌软骨损伤的研究

  目的  探讨扩散张量成像(DTI)及T₂*mapping评估早期髌软骨损伤的临床应用价值。   方法  收集2017年1月—2020年1月温州市中医院行膝关节镜检查Outerbridge分级为Ⅰ、Ⅱ级的早期髌软骨损伤患者32例及髌软骨正常者31例，所有入组对象均行膝关节MRI常规扫描、DTI及T₂*mapping检查。分析早期髌软骨损伤及正常者DTI、T₂*mapping的影像学表现，比较各定量参数的差异并分析DTI、T₂*mapping各定量参数的诊断效能。   结果  对照组及早期损伤组的各向异性分数(FA)、表观弥散系数(ADC)与T₂*值分别为0.42±0.08和0.31±0.09、(1.31±0.17)×10-3 mm2/s和(1.86±0.27)×10-3 mm2/s、(36.40±8.32)ms和(54.39±8.04)ms，各参数2组间比较差异均具有统计学意义(均P < 0.05)。以0.35为阈值时，FA值诊断早期髌软骨损伤的灵敏度、特异度分别为88.3%、83.6%；以1.56×10-3 mm2/s为阈值时，ADC值诊断早期髌软骨损伤的灵敏度、特异度分别为90.6%、84.2%；以46.88 ms为阈值时，T₂*值诊断早期髌软骨损伤的灵敏度、特异度分别为85.4%、80.3%。   结论  多模态MRI成像定量参数对早期髌软骨损伤具有较高的诊断效能，对早期髌软骨损伤的诊断及评估等具有一定的临床应用价值。 

Study of multimode MRI in the diagnosis of early-stage patellar cartilage injury

  Objective  To investigate the diagnostic value of diffusion tensor imaging (DTI) and T₂*mapping in the evaluation of early-stage patellar cartilage injury.   Methods  Thirty-two cases with patellar cartilage injury and 31 cases with normal patellar cartilage were examined through arthroscopy, and their data recorded from January 2017 to January 2020 were obtained. All the subjects underwent MRI conventional scanning, DTI and T₂*mapping examination. The imaging manifestations of DTI and T₂*mapping in early-stage patellar cartilage injury and in the control group were analyzed. Differences among quantitative parameters were determined, and the diagnostic efficacy of quantitative parameters in DTI and T₂*mapping was analyzed.   Results  The fractional anisotropy (FA), apparent diffusion coefficient (ADC) and T₂*value in the early-stage injury group were 0.42±0.08, (1.31±0.17)×10-3 mm2/s and (36.40±8.32) ms, respectively, whereas those in the control group were 0.31±0.09, (1.86±0.27)×10-3 mm2/s and (54.39±8.04) ms, respectively. The differences between the two groups were statistically significant (all P < 0.05). The sensitivity and specificity were 88.3% and 83.6%, and FA threshold was 0.35 in the diagnosis of early-stage patellar cartilage injury. Sensitivity and specificity were 90.6% and 84.2%, respectively, in an ADC threshold of 1.56×10-3 mm2/s and were 85.4% and 80.3%, respectively, in a T₂* threshold of 46.88 ms.   Conclusion  The quantitative parameters of multi-modal MRI have a high diagnostic efficiency for early-stage patellar cartilage injury and have clinical values in the diagnosis and evaluation of patellar cartilage injury.