Dextran-DTPA-Gd磁共振舌间质颈淋巴造影的实验研究

An experimental study of the cervical lymphatic imaging in interstitial magnetic resonance lymphography of tongue using Dextran-DTPA-Gd

目的:探讨Dextran-DTPA-Gd兔舌黏膜下注射后,间质磁共振淋巴造影中颈淋巴显影的应用价值。方法:随机选取纯种成年新西兰大白兔12只,在每只大白兔双侧舌缘黏膜下各注射0.2 mL Dextran-DTPA-Gd,按摩注射部位30s。分别于造影剂注射之前及注射按摩后10、15、20、25、30、35,40、50、90min进行三维增强磁共振淋巴造影成像。测量不同延迟时间引流区颈淋巴结的信号强度,计算不同时间信号强化率(E%),并绘制时间-信号强化率曲线。采用SPSS11.5软件包对数据进行统计学分析。结果:Dextran-DTPA-Gd能够特异性显影兔颈部淋巴结及一、二级淋巴管,显像清晰,血管无显影。颈部淋巴结在注射造影剂后约30min信号强度达到峰值,E%为344%;注射后20～50min可获得最佳强化效果。结论:Dextran-DTPA-Gd作为IMRLG的造影剂,能快速有效地显示颈部引流淋巴管的走行及颈淋巴结形态。

PURPOSE： To explore the application value of the cervical lymphatic imaging in interstitial magnetic resonance lymphography using submucosal injection of Dextran-DTPA-Gd. METHODS： 0.2 mL Dextran-DTPA-Gd （3.96 mmol/L） was injected into the submucosa of the bilateral lingual margins in 12 New Zealand rabbits,and then massaged the injection site for 30 seconds. MR images were obtained before injection and 10, 15, 20, 25, 30, 35, 40, 50, 90 minutes after injection by 3D TOF CE-MRA sequence.The signal intensities of cervical lymph node were measured, the enhancing rates （E%） were calculated and the signal enhancing rates -time curve was drawn. The data was analysed using SPSSll.5 software package. RESULTS： The cervical lymph nodes,the first and second lymphatics were strengthened significantly after injecting Dextran-DTPA-Gd, but the blood vessels were not enhanced at the same time. The enhancing rates of cervical lymph node reached the peak （344%） at 30-min,and the best strengthening effect was achieved between 20-min and 50-min. CONCLUSIONS： As IMRLG contrast agent,the Dextran-DTPA-Gd could image lymphatic drainage lines of the neck and the cervical lymph nodes efficiently.