不同浓度钆喷替酸葡甲胺体外实验及MR直接法膝关节造影的临床研究

目的 探讨不同浓度钆喷替酸葡甲胺(Gd-DTPA)MRI体外信号的变化规律及MR直接法膝关节造影的最佳浓度。方法 配制不同浓度的Gd-DTPA溶液各50ml，采用1．5T MR设备SE序列扫描、观察、测量。然后，选择2mmol／L和100mmol/L浓度Gd-DTPA分别进行直接膝关节造影。结果 Gd-DTPA浓度为2mmol/L时，TlWI信号强度最高；浓度为1．5mmoL／L时，T1WI信号强度最高。T1、T2浓度与信号强度曲线呈“L形”曲线样变化。膝关节直接造影，100mmoL／L浓度Gd-DTPA呈低信号且关节软骨显示清晰，2mmoL／L浓度Gd-DTPA呈高信号且半月板显示清晰。结论 不同浓度Gd-DTPA MRI体外信号变化规律呈“L形”曲线，MR直接法关节造影时，应根据关节病变不同，选择不同浓度的Gd-DTPA。

An in vitro study of Gd-DTPA in different concentrations and clinical study of MR with direct contrast of knee joint

Objective To evaluate the signal changes of Gd-DTPA with different concentrations in vitro and to define the best concentration by using MR with direct contrast of knee joint Methods Different concentrations of 50 ml Gd-DTPA solution were prepared, and they were scanned, observed, and measured by using a 1 5 T MR scanner Direct contrast of knee joint was performed by using Gd-DTPA solution with different concentrations Results The signal intensity was highest by using 2 mmol/l Gd-DTPA solution on T 1WI and 1 5 mmol/l on T 2WI The signal intensity changed with concentration in a parabola pattern After direct injection of contrast into the knee joint, 100 mmol/L Gd-DTPA concentration showed low signal intensity and articular cartilage was distinctly demonstrated, and 2 mmol/L Gd-DTPA concentration showed high signal intensity and semilunar plates were distinctly demonstrated Conclusion The changing pattern of Gd-DTPA in different concentration shows parabola pattern in vitro study When using direct MR articular contrast imaging, Gd-DTPA in different concentration should be chosen according to distinct articular lesion