Department of Radiology, University Medical Center Utrecht, Utrecht, the Netherlands.
Department of Orthopaedics, University Medical Center Utrecht, Utrecht, the Netherlands.
NMR Biomed. 2021 Mar;34(3):e4463. doi: 10.1002/nbm.4463. Epub 2020 Dec 22.
To assess articular cartilage in vivo, a noninvasive measurement is proposed to evaluate damage of the cartilage. It is hypothesized that glycosaminoglycan chemical exchange saturation transfer (gagCEST) can be applied as a noninvasive imaging technique as it would relate to electromechanical indentation and GAG content as measured with biochemical assays. This pilot study applies gagCEST MRI in total knee arthroplasty (TKA) patients to assess substantially damaged articular cartilage. The outcome was verified against electromechanical indentation and biochemical assays to assess the potential of gagCEST MRI. Five TKA patients were scanned on a 7.0 T MRI with a gagCEST sequence. Articular resurfacing cuts after TKA were obtained for electromechanical and biochemical analyses. The gagCEST MRI measurements on the medial condyle showed a moderate correlation with the GAG content, although sensitivity on the lateral condyle was lacking. Additionally, a strong negative correlation of gagCEST MRI with the electromechanical measurements was observed in the regression analysis. Correlation of gagCEST MRI with electromechanical measurements was shown, but the correlation of gagCEST MRI with GAG content was not convincing. In conclusion, gagCEST could be a useful tool to assess the GAG content in articular cartilage noninvasively, although the mismatch in heterogeneity requires further investigation.
为了评估体内的关节软骨，提出了一种非侵入性测量方法来评估软骨的损伤。假设糖胺聚糖化学交换饱和传递（gagCEST）可以作为一种非侵入性成像技术应用，因为它与机电压痕和用生化分析测量的 GAG 含量有关。这项初步研究应用 gagCEST MRI 对全膝关节置换术（TKA）患者进行评估，以评估关节软骨的严重损伤。结果与机电压痕和生化分析进行了验证，以评估 gagCEST MRI 的潜力。对 5 名接受 7.0T MRI 检查的 TKA 患者进行了 gagCEST 序列扫描。在 TKA 后获得关节表面切削的机电和生化分析。内侧髁的 gagCEST MRI 测量值与 GAG 含量有中度相关性，尽管外侧髁的敏感性不足。此外，在回归分析中观察到 gagCEST MRI 与机电测量值之间存在强烈的负相关。虽然 gagCEST MRI 与 GAG 含量的相关性不令人信服，但显示出与机电测量值的相关性。总之，gagCEST 可能是一种有用的工具，可以非侵入性地评估关节软骨中的 GAG 含量，尽管异质性的不匹配需要进一步研究。
