MRI超短回波时间序列评价关节软骨的研究进展

The application of MRI-UTE sequences in evaluation of articular cartilage

关节软骨损伤、变性是骨关节炎(OA)的首要因素,OA早期软骨生化成分最先发生改变,软骨结构逐渐破坏。传统MRI序列的回波时间(TE)较长,采集不到短T_2/T_2~*软骨组织的信号,而超短回波时间(UTE)序列采用超短TE可实现对短T_2/T_2~*的深层软骨和软骨钙化层的直接观察及对其生化组成的定量研究,在探讨OA发生机制及早期诊断中有较好的应用前景。对UTE序列在关节软骨变性早期的定量研究进行综述。

Articular cartilage injury and degeneration is the primary important element in osteoarthritis （OA）. Biochemical components alter at the early stage of OA and followed by the structure destruction. There is a minority of short T2/T2＊components in articular cartilage, however conventional sequences show little or no signal for them because of the long echo times. While ultrashort echo time （UTE） sequences employ relatively short echo times and make it possible to image the short T2/T2＊deep and calcified cartilage layer and to quantify the biochemical components directly, providing a promising method to probe the mechanism and early diagnosis of OA. This review emphasized on applications of UTE sequences in quantification study of early articular cartilage degeneration.