Department of Diagnostic and Interventional Radiology, Medical Faculty, University Hospital Düsseldorf, University Dusseldorf, Moorenstraße 5, 40225, Düsseldorf, Germany.
Department of Orthopedic and Trauma Surgery, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany.
MAGMA. 2021 Apr;34(2):249-260. doi: 10.1007/s10334-020-00868-y. Epub 2020 Jul 28.
To establish and optimize a stable 3 Tesla (T) glycosaminoglycan chemical exchange saturation transfer (gagCEST) imaging protocol for assessing the articular cartilage of the tibiotalar joint in healthy volunteers and patients after a sustained injury to the ankle.
Using Bloch-McConnell simulations, we optimized the sequence protocol for a 3 T MRI scanner for maximum gagCEST effect size within a clinically feasible time frame of less than 07:30 min. This protocol was then used to analyze the gagCEST effect of the articular cartilage of the tibiotalar joint of 17 healthy volunteers and five patients with osteochondral lesions of the talus following ankle trauma. Reproducibility was tested with the intraclass correlation coefficient.
The mean magnetization transfer ratio asymmetry (MTR), i.e., the gagCEST effect size, was significantly lower in patients than in healthy volunteers (0.34 ± 1.9% vs. 1.49 ± 0.11%; p < 0.001 [linear mixed model]). Intra- and inter-rater reproducibility was excellent with an average measure intraclass correlation coefficient (ICC) of 0.97 and a single measure ICC of 0.91 (p < 0.01).
In this feasibility study, pre-morphological tibiotalar joint cartilage damage was quantitatively assessable on the basis of the optimized 3 T gagCEST imaging protocol that allowed stable quantification gagCEST effect sizes across a wide range of health and disease in clinically feasible acquisition times.
建立并优化一种稳定的 3 特斯拉（T）糖胺聚糖化学交换饱和传递（gagCEST）成像方案，用于评估健康志愿者和踝关节持续损伤后患者的距骨下关节软骨。
使用 Bloch-McConnell 模拟，我们针对 3 T MRI 扫描仪优化了序列方案，以在临床可行的不到 07:30 分钟的时间内获得最大的 gagCEST 效果大小。然后，我们使用该方案分析了 17 名健康志愿者和 5 名踝部创伤后距骨骨软骨病变患者的距骨下关节软骨的 gagCEST 效应。使用组内相关系数测试重复性。
患者的平均磁化转移率不对称性（MTR），即 gagCEST 效应大小，显著低于健康志愿者（0.34±1.9%比 1.49±0.11%；p<0.001[线性混合模型]）。平均测量组内相关系数（ICC）为 0.97，单次测量 ICC 为 0.91，表明内和观察者间的可重复性非常好（p<0.01）。
在这项可行性研究中，基于优化的 3 T gagCEST 成像方案，可对距骨下关节软骨进行预形态学定量评估，该方案允许在临床可行的采集时间内稳定地量化 gagCEST 效应大小，涵盖广泛的健康和疾病状态。
