With the development of tissue engineering and regenerative medicine, it is much desired to establish bioimaging techniques to monitor the real-time regeneration efficacy in vivo in a non-invasive way. Herein, we tried magnetic resonance imaging (MRI) to evaluate knee cartilage regeneration after implanting a biomaterial scaffold seeded with chondrocytes, namely, matrix-induced autologous chondrocyte implantation (MACI). After summary of the T2 mapping and the T1-related delayed gadolinium-enhanced MRI imaging of cartilage (dGEMRIC) in vitro and in vivo in the literature, these two MRI techniques were tried clinically. In this study, 18 patients were followed up for 1 year. It was found that there was a significant difference between the regeneration site and the neighboring normal site (control), and the difference gradually diminished with regeneration time up to 1 year according to both the quantitative T1 and T2 MRI methods. We further established the correlation between the quantitative evaluation of MRI and the clinical Lysholm scores for the first time. Hence, the MRI technique was confirmed to be a feasible semi-quantitative yet non-invasive way to evaluate the in vivo regeneration of knee articular cartilage.

中文翻译：

---

磁共振成像用于正常和再生软骨的无创临床评估

随着组织工程和再生医学的发展，迫切需要建立生物成像技术，以无创方式实时监测体内再生效果。在此，我们尝试磁共振成像 (MRI) 来评估植入植入有软骨细胞的生物材料支架后的膝关节软骨再生，即基质诱导的自体软骨细胞植入 (MACI)。在总结了T2映射和T1相关的延迟钆增强软骨MRI成像（dGEMRIC）体外和体内文献后，这两种MRI技术在临床上进行了尝试。本研究对 18 例患者进行了为期 1 年的随访。发现再生位点与相邻的正常位点（对照）有显着差异，根据定量 T1 和 T2 MRI 方法，随着再生时间长达 1 年，差异逐渐减小。我们首次进一步确立了 MRI 定量评价与临床 Lysholm 评分之间的相关性。因此，MRI技术被证实是一种可行的半定量非侵入性评估膝关节软骨体内再生的方法。