Department of Orthopedics, Medical University of Vienna, Austria.
J Magn Reson Imaging. 2010 Mar;31(3):732-9. doi: 10.1002/jmri.22093.
To demonstrate the feasibility of delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) in the ankle at 3 T and to obtain preliminary data on matrix associated autologous chondrocyte (MACI) repair tissue.
A 3D dual flip angle sequence was used with an eight-channel multipurpose coil at 3 T to obtain T1 maps both pre- and postintravenous contrast agent (Magnevist, 0.2 mM/kg). Postcontrast T1 over time was evaluated in three volunteers; a modified dGEMRIC protocol was then used to assess 10 cases after MACI in the ankle.
Forty-five minutes were found sufficient for maximum T1 decrease. MACI cases had a precontrast mean T1 of 1050 +/- 148.4 msec in reference cartilage (RC) and 1080 +/- 165.6 msec in repair tissue (RT). Postcontrast T1 decreased to 590 +/- 134.0 msec in RC and 554 +/- 133.0 msec in RT. There was no significant difference between the delta relaxation rates in RT (9.44 x 10(-4) s(-1)) and RC (8.04 x 10(-4) s(-1), P = 0.487). The mean relative delta relaxation rate was 1.34 +/- 0.83.
It is feasible to assess the thin cartilage layers of the ankle with dGEMRIC at 3 T; MACI can yield RT with properties similar to articular cartilage.
演示在 3T 下对踝关节进行延迟钆增强磁共振成像（dGEMRIC）的可行性，并获得基质相关自体软骨细胞（MACI）修复组织的初步数据。
使用 3T 八通道多用途线圈的 3D 双翻转角序列，在静脉内注射对比剂（Magnevist，0.2mM/kg）前后分别获得 T1 图谱。在 3 个志愿者中评估了对比后 T1 随时间的变化；然后使用改良的 dGEMRIC 方案评估了 10 例踝关节 MACI 后的情况。
发现 45 分钟足以达到最大 T1 降低。MACI 病例的参考软骨（RC）的预对比 T1 平均值为 1050±148.4msec，修复组织（RT）的预对比 T1 平均值为 1080±165.6msec。RC 的对比后 T1 降低至 590±134.0msec，RT 的对比后 T1 降低至 554±133.0msec。RT（9.44×10(-4)s(-1))和 RC（8.04×10(-4)s(-1))的弛豫率差异无统计学意义（P=0.487）。平均相对弛豫率为 1.34±0.83。
在 3T 下评估踝关节的薄软骨层是可行的；MACI 可产生类似于关节软骨的 RT。
